Water-soluble polyvinyl alcohol film with plasticizer blend, related methods, and related articles

ABSTRACT

Disclosed herein are water-soluble films including a polyvinyl alcohol (PVOH) polymer and a combination of at least three plasticizers. The combination of plasticizers includes dipropylene glycol as a first plasticizer, a sugar alcohol such as sorbitol as a second plasticizer, and a polyol such as glycerin as a third plasticizer. When the PVOH polymer and plasticizers are blended in particular proportions and/or selected with regard to various criteria related to physical and chemical film properties, the resulting water-soluble film formed from the PVOH resin blend exhibits beneficial combinations four) of aged tensile strength, aged melting transition delta elevation, aged adhesion value, and/or resistance to seal peeling, which provide strong film seals that retain their water-solubility characteristics.

FIELD OF THE DISCLOSURE

The disclosure relates generally to water-soluble films which include a polyvinyl alcohol (PVOH) resin and a blend of plasticizers, and which can be used for contact with liquids, solids, or combinations thereof. The disclosure further relates to methods of making the films as well as packets and pouches made from the films, which are optionally filled with active components, e.g., detergents, to make measured dose pouches. More particularly, the disclosure relates to such films, packets, and pouches with one or more benefits such as improved physical and chemical properties, in particular improved film seal strength, for end uses and/or resistance to change in solubility characteristics upon contact with chemicals, after sealing to form a packet, or both, together with suitable processability.

BACKGROUND

Water-soluble polymeric films are commonly used as packaging materials to simplify dispersing, pouring, dissolving and dosing of a material to be delivered. For example, packets made from water-soluble film are commonly used to package household care compositions, e.g., a pouch containing a laundry or dish detergent. A consumer can directly add the pouch to a mixing vessel, such as a bucket, sink or washing machine. Advantageously, this provides for accurate dosing while eliminating the need for the consumer to measure the composition. The pouch may also reduce mess that would be associated with dispensing a similar composition from a vessel, such as pouring a liquid laundry detergent from a bottle. The pouch also insulates the composition therein from contact with the user's hands. In sum, soluble polymeric film packets containing pre-measured agents provide for convenience of consumer use in a variety of applications.

Some water-soluble polymeric films that are used to make packets will incompletely dissolve during a wash cycle, leaving film residue on items within the wash. Such problems may particularly arise when the pouch is used under stressed wash conditions, such as when the pouch is used in cold water (e.g., water as low as 5° C. and/or up to 10° C. or 15° C.), in a short wash cycle, and/or in a low-water wash cycle (e.g., wash liquors from about 3 L to about 20 L). Notably, environmental concerns and energy cost are driving consumer desire for utilizing colder wash water and shorter wash cycles.

The formation of water-soluble single unit dose (SUD) pouches includes attachment of at least an upper layer of water soluble film to a lower layer of water-soluble film. In the case of a multi-compartment pouch, it is sometimes desirable to have one pouch compartment separated from a second pouch compartment by a middle layer of water-soluble film, i.e. in so-called superposed multi-compartment pouches. In such a superposed multi-compartment pouch there is a seal between the top film and the middle film, and between the middle film and the bottom film. In another embodiment of a multi-compartment pouch, two pouch compartments are positioned side-by-side, for example including two layers of water-soluble film which are sealed in a middle region between pouch compartments. In such side-by-side pouches, a good seal quality between adjacent compartments is desired to prevent liquid migration from one compartment to the other through the seal. Such pouches known in the art do not have seals as strong as desired. While it is possible to create a strong seal by heat sealing the layers together, this can lead to problems such as weakness at the edge of the heat seal and leaking pouches. Additionally, heat sealing may induce additional crystallinity, resulting in seals that may be less soluble than a corresponding seal produced by solution sealing.

There remains a need for water-soluble films and related packets having the desired characteristics of good water solubility (e.g., cold water solubility), chemical resistance, chemical and physical compatibility with laundry actives, other detergent actives, or other compositions in contact with the film or pouch formed therefrom, and desirable mechanical properties including strong seals, high tensile strength, and good processability. Once formed, whether as a film or a composition-containing pouch formed therefrom, supply chain considerations can result in a substantial passage of time (e.g., at normal or elevated temperatures) before utilization of the end product. Accordingly, there is further a need for improved mechanical properties (e.g., seal strength, tensile strength) after such passage of time and change in film properties.

SUMMARY

The disclosure relates to a water-soluble film (e.g., which can be used to form articles such as pouches or packets) including a polyvinyl alcohol (PVOH) polymer (e.g., one or more PVOH homopolymers, one or more PVOH copolymers, and combinations thereof) and a combination of at least three plasticizers. The combination of plasticizers includes dipropylene glycol as a first plasticizer, a sugar alcohol (e.g. sorbitol) as a second plasticizer, and a polyol (e.g. glycerin) as a third plasticizer. When the PVOH polymer(s) and plasticizers are blended in particular proportions and/or selected with regard to various criteria related to physical and chemical film properties, the resulting water-soluble film formed from the PVOH resin exhibits a beneficial combination (e.g., two, three, or four of) of aged tensile strength, aged melting transition delta elevation, aged adhesion value, and/or resistance to seal peeling. Such combinations of properties provide the ability to form film seals that are strong and that retain their water-solubility characteristics, for example including film-film seals that are formed without heat sealing (e.g., by solvent welding or solvent sealing and/or without application of heat).

One aspect of the disclosure relates to a water-soluble film including a polyvinyl alcohol (PVOH) polymer; dipropylene glycol as a first plasticizer; a sugar alcohol as a second plasticizer; and a polyol as a third plasticizer, the third plasticizer being different from the first plasticizer and the second plasticizer. In a refinement, the water-soluble film includes: the polyvinyl alcohol (PVOH) polymer; dipropylene glycol as the first plasticizer; sorbitol as the second plasticizer; and glycerin as the third plasticizer; wherein the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of about 5 parts to about 50 parts total plasticizer per 100 parts total resin (phr) in the water-soluble film. In another refinement, the first plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In another refinement, the second plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In another refinement, the third plasticizer is present in the water-soluble film in an amount in a range of about 25 wt. % to about 80 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film.

Another aspect of the disclosure relates to an article including a water-soluble film of any of the various disclosed embodiments including a first surface of said film solvent-sealed to a second surface of the same film or to a surface of a second film of any of the various disclosed embodiments.

Another aspect of the disclosure relates to an article including a water-soluble film of any of the various disclosed embodiments in the form of a pouch defining an interior pouch volume (e.g., further comprising a composition, such as a household care composition, contained in the interior pouch volume).

Another aspect of the disclosure relates to a method of forming the articles described herein, where the method includes the steps of: providing the water-soluble film, where the film defines an interior pouch container volume; filling the container volume with a composition (e.g., a household care composition); and sealing the film to form a sealed compartment, wherein the sealed compartment contains the composition.

Another aspect of the disclosure relates to a method of treating a substrate, where the method includes the step of contacting the substrate with an article as described herein.

Another aspect of the disclosure relates to a method for making a water-soluble film, the method including: selecting a polyvinyl alcohol (PVOH) polymer, a first plasticizer, a second plasticizer, and a third plasticizer; selecting a desired range for at least a first film property and a second film property; forming a plurality of water-soluble films comprising the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at different concentrations of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer, wherein at least one of the water-soluble films has a film property within the desired range for each of the first and second film properties; determining the first and second film properties for each of the formed water-soluble films; identifying a film concentration for each of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer from the formed plurality of water-soluble films, the identified film concentration having a first film property and a second film property within the desired range for each property; and forming a film comprising the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at the identified film concentration.

Another aspect of the disclosure relates to use of dipropylene glycol as a plasticizer for a water-soluble polyvinyl alcohol film, in combination with a sugar alcohol plasticizer and a polyol plasticizer, for improving one or more of (a) aged melting transition delta elevation of the film as measured by the Aged Melting Transition Delta Test; (b) aged adhesion value of the film as measured by the Aged Adhesion Test; and (c) aged tensile strength of the film as measured by the Aged Tensile Strength Test.

In a particular refinement of the various embodiments, the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 12° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 1300 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 25 MPa as measured by the Aged Tensile Strength Test. In another refinement, the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 1900 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 30 MPa as measured by the Aged Tensile Strength Test. In another refinement, the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 2500 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 32.5 MPa as measured by the Aged Tensile Strength Test.

For the compositions and methods described herein, optional features, including but not limited to components, compositional ranges thereof, substituents, conditions, and steps, are contemplated to be selected from the various aspects, embodiments, and examples provided herein.

Further aspects and advantages will be apparent to those of ordinary skill in the art from a review of the following detailed description and accompanying drawings. While the compositions and methods are susceptible of embodiments in various forms, the description hereafter includes specific embodiments with the understanding that the disclosure is illustrative, and is not intended to limit the invention to the specific embodiments described herein.

DESCRIPTION OF THE DRAWINGS

The following detailed description of the various disclosed methods, processes, compositions, and articles refers to the accompanying drawings in which:

FIG. 1 is a side cross-sectional view of a water-soluble pouch article including a composition contained therein.

FIG. 2 is a graph illustrating Aged Tensile Strength values as a function of molar volume for PVOH films according to the disclosure incorporating a blend of different plasticizers including glycerin, sorbitol, and an additional plasticizer.

FIG. 3 is a graph illustrating Sum Seal Tear values as a function of molar volume for PVOH films according to the disclosure incorporating a blend of different plasticizers including glycerin, sorbitol, and an additional plasticizer.

FIGS. 4A-4C are a series of simplex contour plots illustrating Aged Melting Transition Delta values (i.e., difference in melting transition value upon film aging), Aged Adhesion values, and Aged Tensile Strength values for a PVOH copolymer blend film according to the disclosure incorporating a blend of different plasticizers ratios including dipropylene glycol, sorbitol, and glycerin at different total plasticizer loadings (4A: 44.4 phr plasticizer loading, 4B: 37.0 phr plasticizer loading, 4C: 29.6 phr plasticizer loading).

FIG. 5 is a simplex plot illustrating plasticizer compositions meeting a first combination of selected Aged Melting Transition Delta values, Aged Adhesion values, and Aged Tensile Strength values for a PVOH copolymer blend film according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 29.6 phr (parts per hundred parts resin, in this case PVOH resin) plasticizer loading.

FIG. 6 is a simplex plot illustrating plasticizer compositions meeting a second combination of selected Aged Melting Transition Delta values, Aged Adhesion values, and Aged Tensile Strength values for a PVOH copolymer blend film according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 29.6 phr plasticizer loading.

FIG. 7 is a simplex plot illustrating plasticizer compositions meeting a third combination of selected Aged Melting Transition Delta values, Aged Adhesion values, and Aged Tensile Strength values for a PVOH copolymer blend film according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 29.6 phr plasticizer loading.

FIG. 8 is a simplex plot illustrating plasticizer compositions meeting a first combination of selected Aged Melting Transition Delta values, Aged Adhesion values, and Aged Tensile Strength values for a PVOH copolymer blend film according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 37.0 phr plasticizer loading.

FIG. 9 includes graphs showing Aged Melting Transition Delta values and Aged Tensile Strength values for PVOH copolymer blend films according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 37.0 phr plasticizer loading.

FIG. 10 includes a graph showing Sum Seal Tears values for PVOH copolymer blend films according to the disclosure incorporating a blend of different plasticizers including dipropylene glycol, sorbitol, and glycerin at a 37.0 phr plasticizer loading.

DETAILED DESCRIPTION

Disclosed herein are water-soluble films including a polyvinyl alcohol polymer and blends of plasticizers including at least dipropylene glycol and one additional plasticizer as described herein, and delivery pouches formed from or otherwise including the films.

Some water-soluble polymeric films that are used to make packets will incompletely dissolve in water during normal use, for example during a laundry wash cycle for packets containing a laundry-related composition (e.g., thereby leaving film residue on items within the wash).

Water-soluble polymeric films based on PVOH can be subject to changes in solubility characteristics. The acetate group in the co-poly(vinyl acetate vinyl alcohol) polymer is known by those skilled in the art to be hydrolysable by either acid or alkaline hydrolysis. As the degree of hydrolysis increases, a polymer composition made from the PVOH homopolymer resin will have increased mechanical strength but reduced solubility at lower temperatures (e.g., requiring hot water temperatures for complete dissolution). Accordingly, exposure of a PVOH homopolymer resin to an alkaline environment (e.g., resulting from a laundry bleaching additive) can transform the resin from one which dissolves rapidly and entirely in a given aqueous environment (e.g., a cold water medium) to one which dissolves slowly and/or incompletely in the aqueous environment, potentially resulting in undissolved polymeric residue at the end of a wash cycle. This is an inherent weakness in the application of films based on just the vinyl acetate/alcohol co-polymer typified by commercial PVOH homopolymer resins.

PVOH copolymer resins with pendant carboxyl groups, such as vinyl alcohol/hydrolyzed methyl acrylate sodium salt resins, can form lactone rings between neighboring pendant carboxyl and alcohol groups, thus reducing the water solubility of the PVOH copolymer resin. In the presence of a strong base such as a laundry bleaching additive, the lactone rings can open over the course of several weeks at relatively warm (ambient) and high humidity conditions (e.g., via lactone ring-opening reactions to form the corresponding pendant carboxyl and alcohol groups with increased water solubility). Thus, contrary to the effect observed with PVOH homopolymer films, it is believed that such a PVOH copolymer film can become more soluble due to chemical interactions between the film and an alkaline composition inside the pouch during storage. Consequently, as they age, the packets may become increasingly prone to premature dissolution during a hot wash cycle (nominally 40° C.), and may in turn decrease the efficacy of certain laundry actives due to the presence of the bleaching agent and the resulting pH influence.

In formulating a suitable film for a given application (e.g., a composition-in-pouch article for a washing operation), multiple factors must be taken in to account, in particular when forming a film-film seal that both is strong and retains its water solubility characteristics. These factors include: (1) aged tensile strength, where a higher aged tensile strength represents stronger pouches in general and stronger pouch seals when the film is the limiting or weakest element of a seal; (2) aged melting transition delta elevation, where a lower melting point elevation upon aging represents prevention of crystalline growth regions (which weaken a seal) and maintenance of amorphous polymer regions (which strengthen a seal); (3) aged adhesion value, where a higher adhesion value is favorable and is representative of seal strength; and (4) a resistance to seal peeling or delamination, where a tendency of a seal to tear instead of peel when a pulling force is applied to the seal represents a high seal strength (e.g., where film mechanical strength is the limiting factor instead of seal strength). Often, water-soluble polymer resins, whether PVOH or otherwise, may have suitable characteristics with respect to some of these factors, but they can have poor characteristics with respect to other of these factors. Accordingly, it would be desirable to provide a water-soluble film in which many, if not all, of these factors have favorable properties in the film, in particular where favorable properties as characterized by the various aging tests at elevated temperatures herein can be representative of similarly favorable properties for films after longer storage times at lower temperatures during actual use.

Accounting for these factors, the present disclosure includes a water-soluble film including a polyvinyl alcohol (PVOH) polymer and a combination of at least three plasticizers. A plasticizer is a liquid, solid, or semi-solid that is added to a material (usually a resin or elastomer) making that material softer, more flexible (by decreasing the glass-transition temperature of the polymer), and easier to process. A polymer can be internally plasticized by chemically modifying the polymer or monomer. In addition or in the alternative, a polymer can be externally plasticized by the addition of a suitable plasticizing agent. The combination of plasticizers for the film described herein includes dipropylene glycol as a first plasticizer, a sugar alcohol as a second plasticizer, and a polyol as a third plasticizer which is different from the first plasticizer and the second plasticizer. In one type of embodiment, the water-soluble film will be substantially free from plasticizers other than the than the first, second, and third plasticizers (e.g., completely free from other plasticizers, or less than about 1 phr of other plasticizers, or less than about 0.5 phr of other plasticizers, or less than about 0.2 phr of other plasticizers). In other embodiments, the water-soluble film can include further plasticizers (e.g., sugar alcohols, polyols, or otherwise) other than the first, second, and third plasticizers. The film optionally can include one or more additional components including fillers, surfactants, and other additives as is known in the art for PVOH films, and as described in more detail below. The sugar alcohol plasticizer can be isomalt, maltitol, sorbitol, xylitol, erythritol, adonitol, dulcitol, pentaerythritol, or mannitol, for example. In a particular aspect, the sugar alcohol plasticizer can be sorbitol or a sorbitol-containing plasticizer such as isomalt. The polyol plasticizer can be glycerin, diglycerin, ethylene glycol, diethylene glycol, triethyleneglycol, tetraethylene glycol, a polyethylene glycol up to 400 MW, neopentyl glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, trimethylolpropane, or a polyether polyol, for example. In a particular aspect, the polyol plasticizer can be glycerin, propylene glycol, or 1,3-propanediol, for example glycerin. In one class of embodiments, the water-soluble film includes the polyvinyl alcohol (PVOH) polymer and a plasticizer blend including dipropylene glycol as the first plasticizer, sorbitol as the second plasticizer, and glycerin as the third plasticizer.

In some embodiments, the water-soluble film can include at least one plasticizer (e.g., as the second plasticizer, the third plasticizer, or otherwise) which is generally solid at room temperature and/or common use, storage, or transportation temperatures, for example a plasticizer which is solid in a range of about 10° C. or 20° C. to about 30° C., 40° C., or 50° C. and/or has a melting point above such range (e.g., a melting point below common film-formation process temperature such as casting, but above common use, storage, or transportation temperatures). Examples of such solid plasticizers include sorbitol (95° C. melting point) and trimethylolpropane (58° C. melting point). Additionally or alternatively, the water-soluble film can include at least one plasticizer (e.g., as the second plasticizer, the third plasticizer, or otherwise) which is generally liquid at room temperature and/or common use, storage, or transportation temperatures, for example which is liquid in a range of about 10° C. or 20° C. to about 30° C., 40° C., or 50° C. and/or has a melting point below such range.

The first, second, and third plasticizers can be present in the water-soluble film in a combined amount in a range of about 5 parts to about 50 parts total plasticizer per 100 parts total resin (phr) in the water-soluble film. In some embodiments, the three plasticizers can be present in the water-soluble film in a combined amount in a range of about 5 phr to about 40 phr, for example about 10 phr, 15 phr or 30 phr to about 40 phr, about 10 phr or 15 phr to about 30 phr or 35 phr, or about 20 phr or 25 phr to about 35 phr. The three plasticizers can be present in any desired relative amount to each other. In various aspects, each of the first, second, and/or third plasticizer individually can be present in the water-soluble film in an amount in a range of about 10 wt. % to about 80 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In an aspect, the first plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film (e.g., at least about 10, 15, or 20 wt. % and/or up to about 20, 30, 40, 50, or 65 wt. %). In another aspect, the second plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film (e.g., e.g., at least about 10, 15, or 20 wt. % and/or up to about 20, 30, 40, 50, or 65 wt. %). In another aspect, the third plasticizer is present in the water-soluble film in an amount in a range of about 25 wt. % to about 80 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film (e.g., at least about 25, 30, 35, or 40 wt. % and/or up to about 50, 60, 70, 75, or 80 wt. %).

Various particular concentration combinations of the first dipropylene glycol plasticizer, the second plasticizer (e.g., sorbitol or otherwise), and the third plasticizer (e.g., glycerin or otherwise) are contemplated.

In one class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 40 wt. % (e.g., about 20 wt. % to 40 wt. %), the second plasticizer is present in the water-soluble film in an amount in a range of about 10 wt. % to about 30 wt. % (e.g., about 10 wt. % to 30 wt. %), and the third plasticizer is present in the water-soluble film in an amount in a range of about 40 wt. % to about 70 wt. % (e.g., about 50 wt. % to 60 wt. %), where each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers can be present in the water-soluble film in a combined amount in a range of about 25 phr to about 40 phr or 45 phr. Films according to these types of embodiments optionally can have an aged tensile strength of at least about 25 MPa or 30 MPa as measured by the Aged Tensile Strength Test (e.g., up to about 30, 35, 38, 40, 45, or 50 MPa). Alternatively or additionally, the films can have a seal tear value of at least about 170% as measured by the Sum Seal Tear Test (e.g., up to about 180% or 200%).

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 46 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 58 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 28 wt. % to about 73 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 25 phr or 30 phr to about 40 phr or 45 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 38 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 16 wt. % to about 58 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 28 wt. % to about 71 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 25 phr or 30 phr to about 40 phr or 45 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 58 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 58 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 28 wt. % to about 73 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 20 phr or 25 phr to about 30 phr or 35 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 50 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 50 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 36 wt. % to about 73 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 20 phr or 25 phr to about 30 phr or 35 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 45 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 19 wt. % to about 52 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 35 wt. % to about 65 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 20 phr or 25 phr to about 30 phr or 35 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 39 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 22 wt. % to about 38 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 39 wt. % to about 64 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 20 phr or 25 phr to about 30 phr or 35 phr.

In another class of embodiments, the first plasticizer is present in the water-soluble film in an amount in a range of about 13 wt. % to about 19 wt. %, the second plasticizer is present in the water-soluble film in an amount in a range of about 41 wt. % to about 52 wt. %, and the third plasticizer is present in the water-soluble film in an amount in a range of about 35 wt. % to about 44 wt. %, wherein each weight concentration is relative to the combined amount of the first, second, and third plasticizers in the water-soluble film. In these types of embodiments, the three plasticizers optionally can be present in the water-soluble film in a combined amount in a range of about 20 phr or 25 phr to about 30 phr or 35 phr.

Various particular aged property combinations of the water-soluble film are contemplated.

In another aspect, the water-soluble film can have at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 12° C. or less as measured by the Aged Melting Transition Delta Test (e.g., about 0, 2, or 4° C. to about 12° C.); (b) an aged adhesion value of at least about 1300 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 25 MPa as measured by the Aged Tensile Strength Test (e.g., up to about 30, 35, 38, 40, 45, or 50 MPa). In one type of embodiment, the film will have properties (a) and (b). In another type of embodiment, the film will have properties (a) and (c). In another type of embodiment, the film will have properties (b) and (c). In another type of embodiment, the film will have all three properties (a), (b), and (c).

In another aspect, the water-soluble film can have at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test (e.g., about 0, 2, or 4° C. to about 11° C.); (b) an aged adhesion value of at least about 1900 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 30 MPa as measured by the Aged Tensile Strength Test (e.g., up to about 35, 38, 40, 45, or 50 MPa). In one type of embodiment, the film will have properties (a) and (b). In another type of embodiment, the film will have properties (a) and (c). In another type of embodiment, the film will have properties (b) and (c). In another type of embodiment, the film will have all three properties (a), (b), and (c).

In another aspect, the water-soluble film can have at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test (e.g., about 0, 2, or 4° C. to about 11° C.); (b) an aged adhesion value of at least about 2500 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 32.5 MPa as measured by the Aged Tensile Strength Test (e.g., up to about 35, 38, 40, 45, or 50 MPa). In one type of embodiment, the film will have properties (a) and (b). In another type of embodiment, the film will have properties (a) and (c). In another type of embodiment, the film will have properties (b) and (c). In another type of embodiment, the film will have all three properties (a), (b), and (c).

The PVOH polymer of the water-soluble film is not particularly limited and it can include a single PVOH homopolymer, a single PVOH copolymer, or a blend of PVOH homopolymers, copolymers, or combinations thereof. In some aspects, the water-soluble film can include a water-soluble polymer which is other than a PVOH polymer. In one class of embodiments, the PVOH polymer will be a partially or fully hydrolyzed PVOH homopolymer including vinyl alcohol monomer units and optionally vinyl acetate monomer units. In another type of embodiment, the PVOH polymer will be a partially or fully hydrolyzed PVOH copolymer including an anionic monomer unit, a vinyl alcohol monomer unit, and optionally a vinyl acetate monomer unit. In various embodiments, the anionic monomer can be one or more of vinyl acetic acid, maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate, dimethyl maleate, maleic anyhydride, fumaric acid, monoalkyl fumarate, dialkyl fumarate, monomethyl fumarate, dimethyl fumarate, fumaric anyhydride, itaconic acid, monomethyl itaconate, dimethyl itaconate, itaconic anhydride, vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali metal salts of the foregoing (e.g., sodium, potassium, or other alkali metal salts), esters of the foregoing (e.g., methyl, ethyl, or other C₁-C₄ or C₆ alkyl esters), and combinations thereof (e.g., multiple types of anionic monomers or equivalent forms of the same anionic monomer). For example, the anionic monomer can include one or more acrylamido methylpropanesulfonic acids (e.g., 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methylacrylamido-2-methylpropanesulfonic acid) and alkali metal salts thereof (e.g., sodium salts). Similarly, the anionic monomer can include one or more of monomethyl maleate and alkali metal salts thereof (e.g., sodium salts). Examples of non-PVOH water-soluble polymers include polyethyleneimines, polyvinyl pyrrolidones, polyalkylene oxides, polyacrylamides, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polyamides, gelatines, methylcelluloses, carboxymethylcelluloses and salts thereof, dextrins, ethylcelluloses, hydroxyethyl celluloses, hydroxypropyl methylcelluloses, maltodextrins, starches, modified starches, guar gum, gum Acacia, xanthan gum, carrageenan, and polyacrylates and salts thereof.

As noted, the PVOH polymer can include blends of PVOH polymers, for example a blend including two or more different PVOH homopolymers, a blend including two or more different PVOH copolymers, or a blend including at least one PVOH homopolymer and at least one PVOH copolymer. In a particular PVOH copolymer blend embodiment, the blend includes a first PVOH copolymer including a first anionic monomer unit, and a second PVOH copolymer including a second anionic monomer unit different from the first anionic monomer unit. For example, the first anionic monomer can include one or more acrylamido methylpropanesulfonic acids and alkali metal salts thereof, and the second anionic monomer can include one or more of monomethyl maleate and alkali metal salts thereof. The first PVOH copolymer can be present in an amount in a range of about 10 wt. % to about 80 wt. % (e.g., 10 wt. % to 60 wt. %, 40 wt. % to 60 wt. %, 10 wt. % to 30 wt. %) of total PVOH polymers in the film, and the second PVOH copolymer can be present in an amount in a range of about 20 wt. % to about 90 wt. % (e.g., 40 wt. % to 90 wt. %, 40 wt. % to 60 wt. %, 70 wt. % to 90 wt. %) of total PVOH polymers in the film.

In an aspect, the disclosure relates to a method for making a water-soluble film including a selected PVOH polymer and three or more plasticizers, for example a first plasticizer (e.g., dipropylene glycol), a second plasticizer (e.g., a sugar alcohol such as sorbitol), and a third plasticizer (e.g., a polyol such as glycerin). In addition to the resin and plasticizer components, desired ranges for at least a first film property and a second film property can be achieved by the teachings herein (e.g., properties such as aged melting transition delta elevation, aged adhesion value, aged adhesion value, and seal tear value). The desired ranges can reflect upper desired boundaries, lower desired boundaries, or a span between lower and upper desired boundaries. Additional film properties beyond the first and second (e.g., third film property, fourth film property, etc.) can be considered when making the film. A plurality of water-soluble films including the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at different concentrations for one or more of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer are then formed (e.g., which further include any other film additives at consistent levels). As illustrated in Example 4, the plurality of water-soluble films can include at least four different films at a given total plasticizer loading (e.g., three film formulations at vertices of a simplex region for the plasticizer composition and at least one film formulation at an interior location of the simplex region). At least one of the water-soluble films will have a film property within the desired range for each of the first and second film properties (e.g., through iteration of formulation variations within the scope of the teachings herein, if necessary). In an aspect, at least one of the water-soluble films also will have a film property outside the desired range for each of the first and second film properties (e.g., to facilitate interpolation of boundaries between desired and undesired composition properties, for example to generate a contour map for the property). For each of the plurality of water-soluble films, the first and second film properties (e.g., and third, fourth, etc. film properties when applicable) are then determined for each of the formed water-soluble films, for example by any suitable analytical technique. After determining the relevant properties for each film, a film concentration is identified for each of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer from the formed plurality of water-soluble films, such that the identified film concentration has a first film property and a second film property (e.g., and third, fourth, etc. film properties when applicable) within the desired range for each property. For example, interpolation or curve-fitting of the film properties of the tested films can be used to generate a map (e.g., a 2D simplex map for a 3-plasticizer system with a fixed level of plasticizer relative to PVOH resin) or other property-film concentration relationship for film concentration selection. A film including the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at the identified film concentration (e.g., in addition to any other film additives used when making the plurality of films) is then formed using any suitable technique (e.g., solution casting, etc.).

The disclosed water-soluble films, delivery pouches including the films, and related methods are contemplated to include embodiments including any combination of one or more of the additional optional elements, features, and steps further described below (including those shown in the figures and examples), unless stated otherwise.

In any embodiment, the water-soluble pouch can contain a composition. The composition can be selected from a liquid, solid or combination thereof. As used herein, “liquid” includes free-flowing liquids, as well as pastes, gels, foams and mousses. Non-limiting examples of liquids include light duty and heavy duty liquid detergent compositions, fabric enhancers, detergent gels commonly used for laundry, bleach and laundry additives. Gases, e.g., suspended bubbles, or solids, e.g. particles, may be included within the liquids. A “solid” as used herein includes, but is not limited to, powders, agglomerates, and mixtures thereof. Non-limiting examples of solids include: granules, micro-capsules, beads, noodles, and pearlized balls. Solid compositions may provide a technical benefit including, but not limited to, through-the-wash benefits, pre-treatment benefits, and/or aesthetic effects.

In any of the laundry-centric embodiments, the composition may be selected from the group of liquid light duty and liquid heavy duty liquid detergent compositions, powdered detergent compositions, fabric enhancers, detergent gels commonly used for laundry, and bleach (e.g., organic or inorganic bleach) and laundry additives, for example.

As used herein, the term “homopolymer” generally includes polymers having a single type of monomeric repeating unit (e.g., a polymeric chain consisting of or consisting essentially of a single monomeric repeating unit). For the particular case of PVOH, the term “homopolymer” (or “PVOH homopolymer”) further includes copolymers having a distribution of vinyl alcohol monomer units and vinyl acetate monomer units, depending on the degree of hydrolysis (e.g., a polymeric chain consisting of or consisting essentially of vinyl alcohol and vinyl acetate monomer units). In the limiting case of 100% hydrolysis, a PVOH homopolymer can include a true homopolymer having only vinyl alcohol units.

As used herein, the term “copolymer” generally includes polymers having two or more types of monomeric repeating units (e.g., a polymeric chain consisting of or consisting essentially of two or more different monomeric repeating units, whether as random copolymers, block copolymers, etc.). For the particular case of PVOH, the term “copolymer” (or “PVOH copolymer”) further includes copolymers having a distribution of vinyl alcohol monomer units and vinyl acetate monomer units, depending on the degree of hydrolysis, as well as at least one other type of monomeric repeating unit (e.g., a ter- (or higher) polymeric chain consisting of or consisting essentially of vinyl alcohol monomer units, vinyl acetate monomer units, and one or more other monomer units, for example anionic monomer units or alkylene (such as ethylene) monomer units). In the limiting case of 100% hydrolysis, a PVOH copolymer can include a copolymer having vinyl alcohol units and one or more other monomer units, but no vinyl acetate units.

As used herein, the term “comprising” indicates the potential inclusion of other agents, elements, steps, or features, in addition to those specified.

As used herein and unless specified otherwise, the terms “wt. %” and “wt %” are intended to refer to the composition of the identified element in “dry” (non water) parts by weight of the entire film (when applicable) or parts by weight of the entire composition enclosed within a pouch (when applicable). As used herein and unless specified otherwise, the term “phr” is intended to refer to the composition of the identified element in parts per one hundred parts water-soluble polymer (or resin; whether PVOH or otherwise) in the water-soluble film.

All ranges set forth herein include all possible subsets of ranges and any combinations of such subset ranges. By default, ranges are inclusive of the stated endpoints, unless stated otherwise. Where a range of values is provided, it is understood that each intervening value between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges, and are also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also contemplated to be part of the disclosure.

Water-Soluble Film Compositions

Water-soluble film compositions, optional ingredients for use therein, and methods of making the same are well known in the art, whether being used for making relatively thin water-soluble films (e.g., as pouch materials) or otherwise.

In one class of embodiments, the water-soluble film includes polyvinyl alcohol (PVOH), including homopolymers thereof (e.g., including substantially only vinyl alcohol and vinyl acetate monomer units), copolymers thereof (e.g., including one or more other monomer units in addition to vinyl alcohol and vinyl acetate units), and mixtures thereof. PVOH is a synthetic resin generally prepared by the alcoholysis, usually termed hydrolysis or saponification, of polyvinyl acetate. Fully hydrolyzed PVOH, wherein virtually all the acetate groups have been converted to alcohol groups, is a strongly hydrogen-bonded, highly crystalline polymer which dissolves only in hot water—greater than about 140° F. (60° C.). If a sufficient number of acetate groups are allowed to remain after the hydrolysis of polyvinyl acetate, the PVOH polymer then being known as partially hydrolyzed, it is more weakly hydrogen-bonded and less crystalline and is soluble in cold water—less than about 50° F. (10° C.). An intermediate cold or hot water soluble film can include, for example, intermediate partially-hydrolyzed PVOH (e.g., with degrees of hydrolysis of about 94% to about 98%), and is readily soluble only in warm water—e.g., rapid dissolution at temperatures of about 40° C. and greater. Both fully and partially hydrolyzed PVOH types are commonly referred to as PVOH homopolymers although the partially hydrolyzed type is technically a vinyl alcohol-vinyl acetate copolymer.

The degree of hydrolysis (DH) of the PVOH polymers and PVOH copolymers included in the water-soluble films of the present disclosure can be in a range of about 75% to about 99% (e.g., about 79% to about 92%, about 86.5% to about 89%, or about 88%, such as for cold-water soluble compositions; about 90% to about 99%, about 92% to about 99%, or about 95% to about 99%). As the degree of hydrolysis is reduced, a film made from the resin will have reduced mechanical strength but faster solubility at temperatures below about 20° C. As the degree of hydrolysis increases, a film made from the polymer will tend to be mechanically stronger and the thermoformability will tend to decrease. The degree of hydrolysis of the PVOH can be chosen such that the water-solubility of the polymer is temperature dependent, and thus the solubility of a film made from the polymer, any compatibilizer polymer, and additional ingredients is also influenced. In one option the film is cold water-soluble. A cold water-soluble film, soluble in water at a temperature of less than 10° C., can include PVOH with a degree of hydrolysis in a range of about 75% to about 90%, or in a range of about 80% to about 90%, or in a range of about 85% to about 90%. In another option the film is hot water-soluble. A hot water-soluble film, soluble in water at a temperature of at least about 60° C., can include PVOH with a degree of hydrolysis of at least about 98%.

Other water soluble polymers for use in addition to the PVOH polymers and PVOH copolymers in the blend can include, but are not limited to modified polyvinyl alcohols, polyacrylates, water-soluble acrylate copolymers, polyvinyl pyrrolidone, polyethyleneimine, pullulan, water-soluble natural polymers including, but not limited to, guar gum, gum Acacia, xanthan gum, carrageenan, and starch, water-soluble polymer derivatives including, but not limited to, modified starches, ethoxylated starch, and hydroxypropylated starch, copolymers of the forgoing and combinations of any of the foregoing. Yet other water-soluble polymers can include polyalkylene oxides, polyacrylamides, polyacrylic acids and salts thereof, celluloses, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polycarboxylic acids and salts thereof, polyaminoacids, polyamides, gelatines, methylcelluloses, carboxymethylcelluloses and salts thereof, dextrins, ethylcelluloses, hydroxyethyl celluloses, hydroxypropyl methylcelluloses, maltodextrins, and polymethacrylates. Such water-soluble polymers, whether PVOH or otherwise are commercially available from a variety of sources. Any of the foregoing water-soluble polymers are generally suitable for use as film-forming polymers. In general, the water-soluble film can include copolymers and/or blends of the foregoing resins.

The water-soluble polymers (e.g., the PVOH polymer or polymers) can be included in the film in an amount in a range of about 30 wt. % or 50 wt. % to about 90 wt. % or 95 wt. %, for example. The weight ratio of the amount of all water-soluble polymers as compared to the combined amount of all plasticizers, compatibilizing agents, and secondary additives can be in a range of about 0.5 to about 18, about 0.5 to about 15, about 0.5 to about 9, about 0.5 to about 5, about 1 to 3, or about 1 to 2, for example. The specific amounts of plasticizers and other non-polymer component can be selected in a particular embodiment based on an intended application of the water-soluble film to adjust film flexibility and to impart processing benefits in view of desired mechanical film properties.

Water-soluble polymers for use in the film described herein (including, but not limited to PVOH polymers and PVOH copolymers) can be characterized by a viscosity in a range of about 3.0 to about 30.0 cP, about 3.0 to about 27.0 cP, about 4.0 to about 24.0 cP, about 4.0 to about 23.0 cP, about 4.0 cP to about 15.0 cP, or about 6.0 to about 10.0 cP, for example at least about 3.0 cP, 4.0 cP, 6.0 cP, 8.0 cP, 10.0 cP, or 12.0 cP and/or up to about 12.0 cP, 16.0 cP, 20.0 cP, 24.0 cP, or 30.0 cP. The viscosity of a polymer is determined by measuring a freshly made solution using a Brookfield LV type viscometer with UL adapter as described in British Standard EN ISO 15023-2:2006 Annex E Brookfield Test method. It is international practice to state the viscosity of 4% aqueous polyvinyl alcohol solutions at 20° C. Polymeric viscosities specified herein in cP should be understood to refer to the viscosity of a 4% aqueous water-soluble polymer solution at 20° C., unless specified otherwise.

It is well known in the art that the viscosity of a water-soluble polymer (PVOH or otherwise) is correlated with the weight-average molecular weight (M _(w)) of the same polymer, and often the viscosity is used as a proxy for M _(w). Thus, the weight-average molecular weight of the water-soluble polymers, including the first PVOH copolymer and the second PVOH polymer or second PVOH copolymer, can be in a range of about 30,000 to about 175,000, or about 30,000 to about 100,000, or about 55,000 to about 80,000, for example.

The water-soluble film can contain other auxiliary agents and processing agents, such as, but not limited to, plasticizers, plasticizer compatibilizers, surfactants, lubricants, release agents, fillers, extenders, cross-linking agents, antiblocking agents, antioxidants, detackifying agents, antifoams, nanoparticles such as layered silicate-type nanoclays (e.g., sodium montmorillonite), bleaching agents (e.g., sodium metabisulfite, sodium bisulfite or others), aversive agents such as bitterants (e.g., denatonium salts such as denatonium benzoate, denatonium saccharide, and denatonium chloride; sucrose octaacetate; quinine; flavonoids such as quercetin and naringen; and quassinoids such as quassin and brucine) and pungents (e.g., capsaicin, piperine, allyl isothiocyanate, and resinferatoxin), and other functional ingredients, in amounts suitable for their intended purposes. Embodiments including plasticizers are preferred. The amount of such agents can be up to about 50 wt. %, 20 wt %, 15 wt %, 10 wt %, 5 wt. %, 4 wt % and/or at least 0.01 wt. %, 0.1 wt %, 1 wt %, or 5 wt %, individually or collectively.

Whether as the first, second, third, or other plasticizer, the plasticizer can include, but is not limited to, glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, sorbitol, 2-methyl-1,3-propanediol, ethanolamines, and a mixture thereof. A preferred plasticizer is glycerin, sorbitol, triethyleneglycol, propylene glycol, dipropylene glycol, 2-methyl-1,3-propanediol, trimethylolpropane, or a combination thereof. The total amount of the plasticizer can be in a range of about 10 wt. % to about 40 wt. %, or about 15 wt. % to about 35 wt. %, or about 20 wt. % to about 30 wt. %, for example about 20 wt. % to about 25 wt. %, based on total film weight. Combinations of glycerin, dipropylene glycol, and sorbitol can be used. Optionally, glycerin can be used in an amount of about 5 wt % or 10 wt. % to about 30 wt %, or 5 wt % or 10 wt. % to about 20 wt %, based on total film weight. Optionally, dipropylene glycol can be used in an amount of about 1 wt. % to about 20 wt. %, or about 2 wt. % or 3 wt. % to about 10 wt. % or 15 wt. %, based on total film weight. Optionally, sorbitol can be used in an amount of about 1 wt % to about 20 wt %, or about 2 wt % or 3 wt. % to about 10 wt % or 15 wt. %, based on total film weight. The specific amounts of plasticizers can be selected in a particular embodiment based on desired film flexibility and processability features of the water-soluble film. At low plasticizer levels, films may become brittle, difficult to process, or prone to breaking. At elevated plasticizer levels, films may be too soft, weak, or difficult to process for a desired use.

Suitable surfactants can include the nonionic, cationic, anionic and zwitterionic classes. Suitable surfactants include, but are not limited to, polyoxyethylenated polyoxypropylene glycols, alcohol ethoxylates, alkylphenol ethoxylates, tertiary acetylenic glycols and alkanolamides (nonionics), polyoxyethylenated amines, quaternary ammonium salts and quaternized polyoxyethylenated amines (cationics), and amine oxides, N-alkylbetaines and sulfobetaines (zwitterionics). Other suitable surfactants include dioctyl sodium sulfosuccinate, lactylated fatty acid esters of glycerol and propylene glycol, lactylic esters of fatty acids, sodium alkyl sulfates, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, lecithin, acetylated fatty acid esters of glycerol and propylene glycol, and acetylated esters of fatty acids, and combinations thereof. In various embodiments, the amount of surfactant in the water-soluble film is in a range of about 0.1 wt % to 2.5 wt %, optionally about 1.0 wt % to 2.0 wt %.

Suitable lubricants/release agents can include, but are not limited to, fatty acids and their salts, fatty alcohols, fatty esters, fatty amines, fatty amine acetates and fatty amides. Preferred lubricants/release agents are fatty acids, fatty acid salts, and fatty amine acetates. In one type of embodiment, the amount of lubricant/release agent in the water-soluble film is in a range of about 0.02 wt % to about 1.5 wt %, optionally about 0.1 wt % to about 1 wt %.

Suitable fillers/extenders/antiblocking agents/detackifying agents include, but are not limited to, starches, modified starches, crosslinked polyvinylpyrrolidone, crosslinked cellulose, microcrystalline cellulose, silica, metallic oxides, calcium carbonate, talc and mica. Preferred materials are starches, modified starches and silica. In one type of embodiment, the amount of filler/extender/antiblocking agent/detackifying agent in the water-soluble film is in a range of about 0.1 wt % to about 25 wt %, or about 1 wt % to about 10 wt %, or about 2 wt. % to about 8 wt. %, or about 3 wt. % to about 5 wt. %. In the absence of starch, one preferred range for a suitable filler/extender/antiblocking agent/detackifying agent is about 0.1 wt % or 1 wt % to about 4 wt % or 6 wt %, or about 1 wt. % to about 4 wt. %, or about 1 wt. % to about 2.5 wt. %.

The water-soluble film can further have a residual moisture content of at least 4 wt. %, for example, or in a range of about 4 to about 10 wt. %, as measured by Karl Fischer titration.

Other features of water-soluble polymer compositions such as films, may be found in U.S. Publication No. 2011/0189413 and U.S. application Ser. No. 13/740,053, both of which are incorporated by reference herein in their entireties.

Method of Making Film

One contemplated class of embodiments is characterized by the water-soluble film being formed by, for example, admixing, co-casting, or welding the PVOH polymer (or PVOH polymers in the case of a blend system) together with the first, second, and third plasticizers along with any optional secondary additives described herein. If the polymers are first admixed then the water-soluble film is preferably formed by casting the resulting admixture (e.g., along with other plasticizers and other additives) to form a film. If the polymers are welded, the water-soluble film can be formed by, for example, solvent or thermal welding. Another contemplated class of embodiments is characterized by the water-soluble film being formed by extrusion, for example, blown extrusion. In one contemplated non-limiting embodiment a PVOH polymer and an acrylamido methylpropanesulfonic acid PVOH terpolymer blended film is formed by blown extrusion.

The film can have any suitable thickness. For example, the film can have a thickness in a range of about 5 to about 200 μm, or in a range of about 20 to about 100 μm, or about 40 to about 85 μm, for example 76 μm.

Optionally, the water-soluble film can be a free-standing film consisting of one layer or a plurality of like layers. Further optionally, the water-soluble film can have at least one layer and can include one or more additional layers of dissimilar composition.

The film is useful for creating a packet to contain a detergent composition comprising cleaning actives thereby forming a pouch. The cleaning actives may take any form such as powders, gels, pastes, liquids, tablets or any combination thereof. The film is also useful for any other application in which improved wet handling and low cold water residues are desired. Embodiments of the film can also exhibit favorable mechanical properties (e.g., seal strength, tensile strength), for example as formed and/or after a period of time under controlled aging conditions. The film forms at least one side wall of the pouch and/or packet, optionally the entire pouch and/or packet, and preferably an outer surface of the at least one sidewall.

The film described herein can also be used to make a packet with two or more compartments made of the same film or in combination with films of other polymeric materials. Additional films can, for example, be obtained by casting, blow-molding, extrusion or blown extrusion of the same or a different polymeric material, as known in the art. In one type of embodiment, the polymers, copolymers or derivatives thereof suitable for use as the additional film are selected from polyvinyl alcohols, polyvinyl pyrrolidone, polyalkylene oxides, polyacrylic acid, cellulose, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polycarboxylic acids and salts, polyaminoacids or peptides, polyamides, polyacrylamide, copolymers of maleic/acrylic acids, polysaccharides including starch and gelatin, natural gums such as xanthan, and carrageenans. For example, polymers can be selected from polyacrylates and water-soluble acrylate copolymers, methylcellulose, carboxymethylcellulose sodium, dextrin, ethylcellulose, hydroxyethyl cellulose, hydroxypropyl methylcellulose, maltodextrin, polymethacrylates, and combinations thereof, or selected from polyvinyl alcohols, polyvinyl alcohol copolymers and hydroxypropyl methyl cellulose (HPMC), and combinations thereof. One contemplated class of embodiments is characterized by the level of polymer in the packet material, for example the PVOH resin blend, as described above, being at least 60%.

Pouches

The pouches of the present disclosure can include at least one sealed compartment. Thus, the pouches may comprise a single compartment or multiple compartments. FIG. 1 illustrates an article in which a water-soluble pouch 100 is formed from water-soluble polymer films 10, 20 sealed at an interface 30. One or both of the films 10, 20 include the PVOH polymer and first, second, and third plasticizers. The films 10, 20 define an interior pouch container volume 40 which contains any desired composition 50 for release into an aqueous environment. The composition 50 is not particularly limited, for example including any of the variety of cleaning compositions described below. In embodiments comprising multiple compartments (not shown), each compartment may contain identical and/or different compositions. In turn, the compositions may take any suitable form including, but not limited to liquid, solid and combinations thereof (e.g. a solid suspended in a liquid). In some embodiments, the pouches comprises a first, second and third compartment, each of which respectively contains a different first, second, and third composition.

The compartments of multi-compartment pouches may be of the same or different size(s) and/or volume(s). The compartments of the present multi-compartment pouches can be separate or conjoined in any suitable manner. In some embodiments, the second and/or third and/or subsequent compartments are superimposed on the first compartment. In one embodiment, the third compartment may be superimposed on the second compartment, which is in turn superimposed on the first compartment in a sandwich configuration. Alternatively the second and third compartments may be superimposed on the first compartment. However it is also equally envisaged that the first, second and optionally third and subsequent compartments may be attached to one another in a side by side relationship. The compartments may be packed in a string, each compartment being individually separable by a perforation line. Hence each compartment may be individually torn-off from the remainder of the string by the end-user, for example, so as to pre-treat or post-treat a fabric with a composition from a compartment. In some embodiments, the first compartment may be surrounded by at least the second compartment, for example in a tire-and-rim configuration, or in a pouch-in-a-pouch configuration.

In some embodiments, multi-compartment pouches comprise three compartments consisting of a large first compartment and two smaller compartments. The second and third smaller compartments are superimposed on the first larger compartment. The size and geometry of the compartments are chosen such that this arrangement is achievable. The geometry of the compartments may be the same or different. In some embodiments the second and optionally third compartment each has a different geometry and shape as compared to the first compartment. In these embodiments, the second and optionally third compartments are arranged in a design on the first compartment. The design may be decorative, educative, or illustrative, for example to illustrate a concept or instruction, and/or used to indicate origin of the product. In some embodiments, the first compartment is the largest compartment having two large faces sealed around the perimeter, and the second compartment is smaller covering less than about 75%, or less than about 50% of the surface area of one face of the first compartment. In embodiments in which there is a third compartment, the aforementioned structure may be the same but the second and third compartments cover less than about 60%, or less than about 50%, or less than about 45% of the surface area of one face of the first compartment.

The pouches and/or packets of the present disclosure may comprise one or more different films. For example, in single compartment embodiments, the packet may be made from one wall that is folded onto itself and sealed at the edges, or alternatively, two walls that are sealed together at the edges. In multiple compartment embodiments, the packet may be made from one or more films such that any given packet compartment may comprise walls made from a single film or multiple films having differing compositions. In one embodiment, a multi-compartment pouch comprises at least three walls: an outer upper wall; an outer lower wall; and a partitioning wall. The outer upper wall and the outer lower wall are generally opposing and form the exterior of the pouch. The partitioning wall is interior to the pouch and is secured to the generally opposing outer walls along a seal line. The partitioning wall separates the interior of the multi-compartment pouch into at least a first compartment and a second compartment.

Pouches and packets may be made using any suitable equipment and method. For example, single compartment pouches may be made using vertical form filling, horizontal form filling, or rotary drum filling techniques commonly known in the art. Such processes may be either continuous or intermittent. The film may be dampened, and/or heated to increase the malleability thereof. The method may also involve the use of a vacuum to draw the film into a suitable mold. The vacuum drawing the film into the mold can be applied for about 0.2 to about 5 seconds, or about 0.3 to about 3, or about 0.5 to about 1.5 seconds, once the film is on the horizontal portion of the surface. This vacuum can be such that it provides an under-pressure in a range of 10 mbar to 1000 mbar, or in a range of 100 mbar to 600 mbar, for example.

The molds, in which packets may be made, can have any shape, length, width and depth, depending on the required dimensions of the pouches. The molds may also vary in size and shape from one to another, if desirable. For example, the volume of the final pouches may be about 5 ml to about 300 ml, or about 10 to 150 ml, or about 20 to about 100 ml, and that the mold sizes are adjusted accordingly.

In one embodiment, the packet comprises a first and a second sealed compartment. The second compartment is in a generally superposed relationship with the first sealed compartment such that the second sealed compartment and the first sealed compartment share a partitioning wall interior to the pouch.

In one embodiment, the packet comprising a first and a second compartment further comprises a third sealed compartment. The third sealed compartment is in a generally superposed relationship with the first sealed compartment such that the third sealed compartment and the first sealed compartment share a partitioning wall interior to the pouch.

In some embodiments, the first composition and the second composition are selected from one of the following combinations: liquid, liquid; liquid, powder; powder, powder; and powder, liquid.

In some embodiments, the first, second and third compositions are selected from one of the following combinations: solid, liquid, liquid and liquid, liquid, liquid.

In one embodiment, the single compartment or plurality of sealed compartments contains a composition. The plurality of compartments may each contain the same or a different composition. The composition is selected from a liquid, solid or combination thereof.

In one embodiment, the composition may be selected from the group of liquid light duty and liquid heavy duty liquid detergent compositions, powdered detergent compositions, dish detergent for hand washing and/or machine washing; hard surface cleaning compositions, fabric enhancers, detergent gels commonly used for laundry, and bleach and laundry additives, shampoos, and body washes.

Shaping, Sealing, and Thermoforming

A contemplated class of embodiments is characterized by good thermoformability of the water-soluble film made as described herein. A thermoformable film is one that can be shaped through the application of heat and a force.

Thermoforming a film is the process of heating the film, shaping it in a mold, and then allowing the film to cool, whereupon the film will hold the shape of the mold. The heat may be applied using any suitable means. For example, the film may be heated directly by passing it under a heating element or through hot air, prior to feeding it onto a surface or once on a surface. Alternatively, it may be heated indirectly, for example by heating the surface or applying a hot item onto the film. In some embodiments, the film is heated using an infrared light. The film may be heated to a temperature of about 50 to about 150° C., about 50 to about 120° C., about 60 to about 130° C., about 70 to about 120° C., or about 60 to about 90° C. Thermoforming can be performed by any one or more of the following processes: the manual draping of a thermally softened film over a mold, or the pressure induced shaping of a softened film to a mold (e.g., vacuum forming), or the automatic high-speed indexing of a freshly extruded sheet having an accurately known temperature into a forming and trimming station, or the automatic placement, plug and/or pneumatic stretching and pressuring forming of a film.

Alternatively, the film can be wetted by any suitable means, for example directly by spraying a wetting agent (including water, a solution of the film composition, a plasticizer for the film composition, or any combination of the foregoing) onto the film, prior to feeding it onto the surface or once on the surface, or indirectly by wetting the surface or by applying a wet item onto the film.

Once a film has been heated and/or wetted, it may be drawn into an appropriate mold, preferably using a vacuum. The filling of the molded film can be accomplished by utilizing any suitable means. In some embodiments, the most preferred method will depend on the product form and required speed of filling. In some embodiments, the molded film is filled by in-line filling techniques. The filled, open packets are then closed forming the pouches, using a second film, by any suitable method. This may be accomplished while in horizontal position and in continuous, constant motion. The closing may be accomplished by continuously feeding a second film, preferably water-soluble film, over and onto the open packets and then preferably sealing the first and second film together, typically in the area between the molds and thus between the packets.

Any suitable method of sealing the packet and/or the individual compartments thereof may be utilized. Non-limiting examples of such means include heat sealing, solvent welding, solvent or wet sealing, and combinations thereof. Typically, only the area which is to form the seal is treated with heat or solvent. The heat or solvent can be applied by any method, typically on the closing material, and typically only on the areas which are to form the seal. If solvent or wet sealing or welding is used, it may be preferred that heat is also applied. Preferred wet or solvent sealing/welding methods include selectively applying solvent onto the area between the molds, or on the closing material, by for example, spraying or printing this onto these areas, and then applying pressure onto these areas, to form the seal. Sealing rolls and belts as described above (optionally also providing heat) can be used, for example. One type of embodiment made particularly advantageous by the present disclosure is sealing the film to itself of another similar film by solvent sealing, optionally without heat.

The formed pouches may then be cut by a cutting device. Cutting can be accomplished using any known method. It may be preferred that the cutting is also done in continuous manner, and preferably with constant speed and preferably while in horizontal position. The cutting device can, for example, be a sharp item, or a hot item, or a laser, whereby in the latter cases, the hot item or laser ‘burns’ through the film/sealing area.

The different compartments of a multi-compartment pouches may be made together in a side-by-side style wherein the resulting, cojoined pouches may or may not be separated by cutting. Alternatively, the compartments can be made separately.

In some embodiments, pouches may be made according to a process comprising the steps of: a) forming a first compartment (as described above); b) forming a recess within some or all of the closed compartment formed in step (a), to generate a second molded compartment superposed above the first compartment; c) filling and closing the second compartments by means of a third film; d) sealing the first, second and third films; and e) cutting the films to produce a multi-compartment pouch. The recess formed in step (b) may be achieved by applying a vacuum to the compartment prepared in step (a).

In some embodiments, second, and/or third compartment(s) can be made in a separate step and then combined with the first compartment as described in European Patent Application Number 08101442.5 or WO 2009/152031.

In some embodiments, pouches may be made according to a process comprising the steps of: a) forming a first compartment, optionally using heat and/or vacuum, using a first film on a first forming machine; b) filling the first compartment with a first composition; c) on a second forming machine, deforming a second film, optionally using heat and vacuum, to make a second and optionally third molded compartment; d) filling the second and optionally third compartments; e) sealing the second and optionally third compartment using a third film; f) placing the sealed second and optionally third compartments onto the first compartment; g) sealing the first, second and optionally third compartments; and h) cutting the films to produce a multi-compartment pouch.

The first and second forming machines may be selected based on their suitability to perform the above process. In some embodiments, the first forming machine is preferably a horizontal forming machine, and the second forming machine is preferably a rotary drum forming machine, preferably located above the first forming machine.

It should be understood that by the use of appropriate feed stations, it may be possible to manufacture multi-compartment pouches incorporating a number of different or distinctive compositions and/or different or distinctive liquid, gel or paste compositions.

In some embodiments, the film and/or pouch is sprayed or dusted with a suitable material, such as an active agent, a lubricant, an aversive agent, or mixtures thereof. In some embodiments, the film and/or pouch is printed upon, for example, with an ink and/or an active agent.

Pouch Contents

The present articles (e.g., in the form of pouches or packets) may contain various compositions, for example household care compositions. A multi-compartment pouch may contain the same or different compositions in each separate compartment. The composition is proximal to the water-soluble film. The composition may be less than about 10 cm, or less than about 5 cm, or less than about 1 cm from the film. Typically the composition is adjacent to the film or in contact with the film. The film may be in the form of a pouch or a compartment, containing the composition therein.

As described above, the film and pouch are particularly advantageous for packaging (e.g., in direct contact with) materials which have exchangeable hydrogen ions, for example compositions characterized by acid/base equilibria, such as amine-fatty acid equilibria and/or amine-anionic surfactant acid equilibria.

This feature of the disclosure may be utilized to keep compositions containing incompatible ingredients (e.g., bleach and enzymes) physically separated or partitioned from each other. It is believed that such partitioning may expand the useful life and/or decrease physical instability of such ingredients. Additionally or alternatively, such partitioning may provide aesthetic benefits as described in European Patent Application Number 09161692.0.

Non-limiting examples of useful compositions (e.g., household care compositions) include light duty and heavy duty liquid detergent compositions, hard surface cleaning compositions, detergent gels commonly used for laundry, bleach and laundry additives, fabric enhancer compositions (such as fabric softeners), shampoos, body washes, and other personal care compositions. Compositions of use in the present pouches may take the form of a liquid, solid or a powder. Liquid compositions may comprise a solid. Solids may include powder or agglomerates, such as micro-capsules, beads, noodles or one or more pearlized balls or mixtures thereof. Such a solid element may provide a technical benefit, through the wash or as a pre-treat, delayed or sequential release component; additionally or alternatively, it may provide an aesthetic effect.

The compositions encapsulated by the films described herein can have any suitable viscosity depending on factors such as formulated ingredients and purpose of the composition. In one embodiment, the composition has a high shear viscosity value, at a shear rate of 20 s⁻¹ and a temperature of 20° C., of 100 to 3,000 cP, alternatively 300 to 2,000 cP, alternatively 500 to 1,000 cP, and a low shear viscosity value, at a shear rate of 1 s⁻¹ and a temperature of 20° C., of 500 to 100,000 cP, alternatively 1000 to 10,000 cP, alternatively 1,300 to 5,000 cP. Methods to measure viscosity are known in the art. According to the present invention viscosity measurements are carried out using a rotational rheometer e.g. TA instruments AR550. The instrument includes a 40 mm 2° or 1° cone fixture with a gap of around 50-60 μm for isotropic liquids, or a 40 mm flat steel plate with a gap of 1000 μm for particles containing liquids. The measurement is carried out using a flow procedure that contains a conditioning step, a peak hold and a continuous ramp step. The conditioning step involves the setting of the measurement temperature at 20° C., a pre-shear of 10 seconds at a shear rate of 10 s⁻¹, and an equilibration of 60 seconds at the selected temperature. The peak hold involves applying a shear rate of 0.05 s⁻¹ at 20° C. for 3 min with sampling every 10 s. The continuous ramp step is performed at a shear rate from 0.1 to 1200 s⁻¹ for 3 min at 20° C. to obtain the full flow profile.

In pouches comprising laundry, laundry additive and/or fabric enhancer compositions, the compositions may comprise one or more of the following non-limiting list of ingredients: fabric care benefit agent; detersive enzyme; deposition aid; rheology modifier; builder; bleach; bleaching agent; bleach precursor; bleach booster; bleach catalyst; perfume and/or perfume microcapsules (see for example U.S. Pat. No. 5,137,646); perfume loaded zeolite; starch encapsulated accord; polyglycerol esters; whitening agent; pearlescent agent; enzyme stabilizing systems; scavenging agents including fixing agents for anionic dyes, complexing agents for anionic surfactants, and mixtures thereof; optical brighteners or fluorescers; polymer including but not limited to soil release polymer and/or soil suspension polymer; dispersants; antifoam agents; non-aqueous solvent; fatty acid; suds suppressors, e.g., silicone suds suppressors (see: U.S. Publication No. 2003/0060390 A1, ¶65-77); cationic starches (see: US 2004/0204337 A1 and US 2007/0219111 A1); scum dispersants (see: US 2003/0126282 A1, ¶89-90); substantive dyes; hueing dyes (see: US 2014/0162929A1); colorants; opacifier; antioxidant; hydrotropes such as toluenesulfonates, cumenesulfonates and naphthalenesulfonates; color speckles; colored beads, spheres or extrudates; clay softening agents; anti-bacterial agents. Any one or more of these ingredients is further described in described in European Patent Application Number 09161692.0, U.S. Publication Number 2003/0139312A1 and U.S. Patent Application No. 61/229,981. Additionally or alternatively, the compositions may comprise surfactants, quaternary ammonium compounds, and/or solvent systems. Quaternary ammonium compounds may be present in fabric enhancer compositions, such as fabric softeners, and comprise quaternary ammonium cations that are positively charged polyatomic ions of the structure NR₄ ⁺, where R is an alkyl group or an aryl group.

Surfactants

The detergent compositions can comprise from about 1% to 80% by weight of a surfactant. Surfactant is particularly preferred as a component of the first composition. Preferably, the first composition comprises from about 5% to 50% by weight of surfactant. The second and third compositions may comprise surfactant at levels of from 0.1 to 99.9%.

Detersive surfactants utilized can be of the anionic, nonionic, zwitterionic, ampholytic or cationic type or can comprise compatible mixtures of these types. More preferably surfactants are selected from the group consisting of anionic, nonionic, cationic surfactants and mixtures thereof. Preferably the compositions are substantially free of betaine surfactants. Detergent surfactants useful herein are described in U.S. Pat. Nos. 3,664,961; 3,919,678; 4,222,905; and 4,239,659. Anionic and nonionic surfactants are preferred.

Useful anionic surfactants can themselves be of several different types. For example, water-soluble salts of the higher fatty acids, i.e., “soaps”, are useful anionic surfactants in the compositions herein. This includes alkali metal soaps such as the sodium, potassium, ammonium, and alkyl ammonium salts of higher fatty acids containing from about 8 to about 24 carbon atoms, and preferably from about 12 to about 18 carbon atoms. Soaps can be made by direct saponification of fats and oils or by the neutralization of free fatty acids. Particularly useful are the sodium and potassium salts of the mixtures of fatty acids derived from coconut oil and tallow, i.e., sodium or potassium tallow and coconut soap.

Additional non-soap anionic surfactants which are suitable for use herein include the water-soluble salts, preferably the alkali metal, and ammonium salts, of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term “alkyl” is the alkyl portion of acyl groups.) Examples of this group of synthetic surfactants include: a) the sodium, potassium and ammonium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C₈-C₁₈) such as those produced by reducing the glycerides of tallow or coconut oil; b) the sodium, potassium and ammonium alkyl polyethoxylate sulfates, particularly those in which the alkyl group contains from 10 to 22, preferably from 12 to 18 carbon atoms, and wherein the polyethoxylate chain contains from 1 to 15, preferably 1 to 6 ethoxylate moieties; and c) the sodium and potassium alkylbenzene sulfonates in which the alkyl group contains from about 9 to about 15 carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Pat. Nos. 2,220,099 and 2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to 13, abbreviated as C₁₁-C₁₃ LAS.

Preferred nonionic surfactants are those of the formula R₁(OC₂H₄)_(n)OH, wherein R₁ is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkyl phenyl group, and n is from 3 to about 80. Particularly preferred are condensation products of C₁₂-C₁₅ alcohols with from about 5 to about 20 moles of ethylene oxide per mole of alcohol, e.g., C₁₂-C₁₃ alcohol condensed with about 6.5 moles of ethylene oxide per mole of alcohol.

Solvent System

The solvent system in the present compositions can be a solvent system containing water alone or mixtures of organic solvents with water. Preferred organic solvents include 1,2-propanediol, ethanol, glycerol, dipropylene glycol, methyl propane diol and mixtures thereof. Other lower alcohols, C₁-C₄ alkanolamines such as monoethanolamine and triethanolamine, can also be used. Solvent systems can be absent, for example from anhydrous solid embodiments of the disclosure, but more typically are present at levels in the range of from about 0.1% to about 98%, preferably at least about 1% to about 50%, more usually from about 5% to about 25%. Typically, the present compositions, particularly when in liquid form, comprise less than 50% water, preferably from about 0.1% to about 20% water, or more preferably from about 0.5% to about 15%, or from about 5% to about 12%, by weight of the composition, of water.

The compositions herein can generally be prepared by mixing the ingredients together. If a pearlescent material is used it should be added in the late stages of mixing. If a rheology modifier is used, it is preferred to first form a pre-mix within which the rheology modifier is dispersed in a portion of the water and optionally other ingredients eventually used to comprise the compositions. This pre-mix is formed in such a way that it forms a structured liquid. To this structured pre-mix can then be added, while the pre-mix is under agitation, the surfactant(s) and essential laundry adjunct materials, along with water and whatever optional detergent composition adjuncts are to be used.

The pH of the useful compositions may be from about 2 to about 12, about 4 to about 12, about 5.5 to about 9.5, about 6 to about 8.5, or about 6.5 to about 8.2. Laundry detergent compositions may have a pH of about 6 to about 10, about 6.5 to about 8.5, about 7 to about 7.5, or about 8 to about 10. Auto-dishwashing compositions may have a pH of about 8 to about 12. Laundry detergent additive compositions may have a pH of about 4 to about 8. Fabric enhancers may have a pH of from about 2 or 4 to about 8, or from about 2 to about 4, or from about 2.5 to about 3.5, or from about 2.7 to about 3.3.

The pH of the detergent is defined as the pH of an aqueous 10% (weight/volume) solution of the detergent at 20±2° C.; for solids and powdered detergent this is defined as the pH of an aqueous 1% (weight/volume) solution of the detergent at 20±2° C. Any meter capable of measuring pH to ±0.01 pH units is suitable. Orion meters (Thermo Scientific, Clintinpark-Keppekouter, Ninovesteenweg 198, 9320 Erembodegem-Aalst, Belgium) or equivalent are acceptable instruments. The pH meter should be equipped with a suitable glass electrode with calomel or silver/silver chloride reference. An example includes Mettler DB 115. The electrode shall be stored in the manufacturer's recommended electrolyte solution.

The 10% aqueous solution of the detergent is prepared according to the following procedure. A sample of 10±0.05 grams is weighted with a balance capable of accurately measuring to ±0.02 grams. The sample is transferred to a 100 mL volumetric flask, diluted to volume with purified water (deionized and/or distilled water are suitable as long as the conductivity of the water is <5 μS/cm), and thoroughly mixed. About 50 mL of the resulting solution is poured into a beaker, the temperature is adjusted to 20±2° C. and the pH is measured according to the standard procedure of the pH meter manufacturer (it is critical to follow the manufacturer's instructions to also set up and calibrate the pH assembly).

For solid and powdered detergents, the 1% aqueous solution of the detergent is prepared according to the following procedure. A sample of 10±0.05 grams is weighted with a balance capable of accurately measuring to ±0.02 grams. The sample is transferred to a volumetric flask of 1000 mL, diluted to volume with purified water (deionized and/or distilled water are suitable as long as the conductivity of the water is <5 μS/cm), and thoroughly mixed. About 50 mL of the resulting solution is poured into a beaker, the temperature is adjusted to 20±2° C. and the pH is measured according to the standard procedure of the pH meter manufacturer (it is critical to follow the manufacturer's instructions to also set up and calibrate the pH assembly).

Bleaches

Inorganic and organic bleaches are suitable cleaning actives for use herein. Inorganic bleaches include perhydrate salts such as perborate, percarbonate, perphosphate, persulfate and persilicate salts. The inorganic perhydrate salts are normally the alkali metal salts. The inorganic perhydrate salt may be included as the crystalline solid without additional protection. Alternatively, the salt can be coated as is known in the art.

Alkali metal percarbonates, particularly sodium percarbonate are preferred perhydrates for use in the detergent composition described herein. The percarbonate is most preferably incorporated into the products in a coated form which provides in-product stability. A suitable coating material providing in product stability comprises mixed salt of a water-soluble alkali metal sulphate and carbonate. Such coatings together with coating processes have previously been described in GB1,466,799, and U.S. Pat. Nos. 3,975,280; 4,075,116; and 5,340,496, each incorporated herein by reference. The weight ratio of the mixed salt coating material to percarbonate lies in the range from 1:99 to 1:9, and preferably from 1:49 to 1:19. Preferably, the mixed salt is of sodium sulphate and sodium carbonate which has the general formula Na₂SO₄.n.Na₂CO₃ wherein n is from 0.1 to 3, preferably from 0.3 to 1.0, and more preferably from 0.2 to 0.5. Another suitable coating material providing in product stability comprises sodium silicate of SiO₂:Na₂O ratio from 1.8:1 to 3.0:1, preferably 1.8:1 to 2.4:1, and/or sodium metasilicate, preferably applied at a level of from 2% to 10%, (normally from 3% to 5%) of SiO₂ by weight of the inorganic perhydrate salt, such as potassium peroxymonopersulfate. Other coatings which contain magnesium silicate, silicate and borate salts, silicate and boric acids, waxes, oils, and fatty soaps can also be used advantageously

Organic bleaches can include organic peroxyacids including diacyl and tetraacylperoxides, especially diperoxydodecanedioc acid, diperoxytetradecanedioc acid, and diperoxyhexadecanedioc acid. Dibenzoyl peroxide is a preferred organic peroxyacid herein. The diacyl peroxide, especially dibenzoyl peroxide, preferably can be present in the form of particles having a weight average diameter of from about 0.1 to about 100 microns, preferably from about 0.5 to about 30 microns, more preferably from about 1 to about 10 microns. Preferably, at least about 25% to 100%, more preferably at least about 50%, even more preferably at least about 75%, most preferably at least about 90%, of the particles are smaller than 10 microns, preferably smaller than 6 microns.

Other organic bleaches include the peroxy acids, particular examples being the alkylperoxy acids and the arylperoxy acids. Preferred representatives are: (a) peroxybenzoic acid and its ring-substituted derivatives, such as alkylperoxybenzoic acids, but also peroxy-α-naphthoic acid and magnesium monoperphthalate; (b) the aliphatic or substituted aliphatic peroxy acids, such as peroxylauric acid, peroxystearic acid, ε-phthalimidoperoxycaproic acid[phthaloiminoperoxyhexanoic acid (PAP)], o-carboxybenzamidoperoxycaproic acid, N-nonenylamidoperadipic acid and N-nonenylamidopersuccinates; and (c) aliphatic and araliphatic peroxydicarboxylic acids, such as 1,12-diperoxycarboxylic acid, 1,9-diperoxyazelaic acid, diperoxysebacic acid, diperoxybrassylic acid, the diperoxyphthalic acids, 2-decyldiperoxybutane-1,4-dioic acid, N,N-terephthaloyldi(6-aminopercaproic acid)

Bleach activators can include organic peracid precursors that enhance the bleaching action in the course of cleaning at temperatures of 60° C. and below. Bleach activators suitable for use herein include compounds which, under perhydrolysis conditions, give aliphatic peroxoycarboxylic acids having preferably from 1 to 10 carbon atoms, in particular from 2 to 4 carbon atoms, and/or optionally substituted perbenzoic acid. Suitable substances bear O-acyl and/or N-acyl groups of the number of carbon atoms specified and/or optionally substituted benzoyl groups. Preference is given to polyacylated alkylenediamines, in particular tetraacetylethylenediamine (TAED), acylated triazine derivatives, in particular 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycolurils, in particular tetraacetylglycoluril (TAGU), N-acylimides, in particular N-nonanoylsuccinimide (NOSI), acylated phenolsulfonates, in particular n-nonanoyl- or isononanoyloxybenzenesulfonate (n- or iso-NOBS), carboxylic anhydrides, in particular phthalic anhydride, acylated polyhydric alcohols, in particular triacetin, ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran and also triethylacetyl citrate (TEAC).

Bleach catalysts preferred for use in the detergent composition herein include the manganese triazacyclononane and related complexes (U.S. Pat. Nos. 4,246,612, 5,227,084); Co, Cu, Mn and Fe bispyridylamine and related complexes (U.S. Pat. No. 5,114,611); and pentamine acetate cobalt(III) and related complexes (U.S. Pat. No. 4,810,410). A complete description of bleach catalysts suitable for use herein can be found in U.S. Pat. No. 6,599,871, incorporated herein by reference.

Dishwashing Agents

A preferred surfactant for use in automatic dishwashing detergents is low foaming by itself or in combination with other components (e.g. suds suppressers). Preferred for use herein are low and high cloud point nonionic surfactants and mixtures thereof including nonionic alkoxylated surfactants (especially ethoxylates derived from C₆-C₁₈ primary alcohols), ethoxylated-propoxylated alcohols (e.g., Olin Corporation's POLY-TERGENT® SLF18), epoxy-capped poly(oxyalkylated) alcohols (e.g., Olin Corporation's POLY-TERGENT® SLF18B—see WO-A-94/22800), ether-capped poly(oxyalkylated) alcohol surfactants, and block polyoxyethylene-polyoxypropylene polymeric compounds such as PLURONIC®, REVERSED PLURONIC®, and TETRONIC® by the BASF-Wyandotte Corp., Wyandotte, Mich.; amphoteric surfactants such as the C₁₂-C₂₀ alkyl amine oxides (preferred amine oxides for use herein include lauryldimethyl amine oxide and hexadecyl dimethyl amine oxide), and alkyl amphocarboxylic surfactants such as MIRANOL™ C2M; and zwitterionic surfactants such as the betaines and sultaines; and mixtures thereof. Surfactants suitable for use herein are disclosed, for example, in U.S. Pat. Nos. 3,929,678, 4,259,217, EP-A-0414 549, WO-A-93/08876 and WO-A-93/08874. Surfactants can be present at a level of from about 0.2% to about 30% by weight, more preferably from about 0.5% to about 10% by weight, most preferably from about 1% to about 5% by weight of a detergent composition.

Other Compositions and Additives

Builders suitable for use in the detergent composition described herein include water-soluble builders, including citrates, carbonates, silicate and polyphosphates, e.g. sodium tripolyphosphate and sodium tripolyphosphate hexahydrate, potassium tripolyphosphate and mixed sodium and potassium tripolyphosphate salts.

Enzymes suitable for use in the detergent composition described herein include bacterial and fungal cellulases including CAREZYME and CELLUZYME (Novo Nordisk A/S); peroxidases; lipases including AMANO-P (Amano Pharmaceutical Co.), M1 LIPASE and LIPOMAX (Gist-Brocades) and LIPOLASE and LIPOLASE ULTRA (Novo); cutinases; proteases including ESPERASE, ALCALASE, DURAZYM and SAVINASE (Novo) and MAXATASE, MAXACAL, PROPERASE and MAXAPEM (Gist-Brocades); cc and 13 amylases including PURAFECT OX AM (Genencor) and TERMAMYL, BAN, FUNGAMYL, DURAMYL, and NATALASE (Novo); pectinases; and mixtures thereof. Enzymes can be added herein as prills, granulates, or cogranulates at levels typically in the range from about 0.0001% to about 2% pure enzyme by weight of the cleaning composition.

Suds suppressers suitable for use in the detergent composition described herein include nonionic surfactants having a low cloud point. “Cloud point” as used herein, is a well known property of nonionic surfactants which is the result of the surfactant becoming less soluble with increasing temperature, the temperature at which the appearance of a second phase is observable is referred to as the “cloud point.” As used herein, a “low cloud point” nonionic surfactant is defined as a nonionic surfactant system ingredient having a cloud point of less than 30° C., preferably less than about 20° C., and even more preferably less than about 10° C., and most preferably less than about 7.5° C. Low cloud point nonionic surfactants can include nonionic alkoxylated surfactants, especially ethoxylates derived from primary alcohol, and polyoxypropylene/polyoxyethylene/polyoxypropylene (PO/EO/PO) reverse block polymers. Also, such low cloud point nonionic surfactants can include, for example, ethoxylated-propoxylated alcohol (e.g., BASF POLY-TERGENT SLF18) and epoxy-capped poly(oxyalkylated) alcohols (e.g., BASF POLY-TERGENT SLF18B series of nonionics, as described, for example, in U.S. Pat. No. 5,576,281).

Other suitable components for use in the detergent composition described herein include cleaning polymers having anti-redeposition, soil release or other detergency properties. Anti-redeposition polymers for use herein include acrylic acid containing polymers such as SOKALAN PA30, PA20, PA15, PA10 and SOKALAN CP10 (BASF GmbH), ACUSOL 45N, 480N, 460N (Rohm and Haas), acrylic acid/maleic acid copolymers such as SOKALAN CP5 and acrylic/methacrylic copolymers. Other suitable polymers include amine-based polymers such as alkoxylated polyalkyleneimines (e.g., PEI600 E020 and/or ethoxysulfated hexamethylene diamine dimethyl quats), which, optionally, may be quaternized. Soil release polymers for use herein include alkyl and hydroxyalkyl celluloses (U.S. Pat. No. 4,000,093), polyoxyethylenes, polyoxypropylenes and copolymers thereof, and nonionic and anionic polymers based on terephthalate esters of ethylene glycol, propylene glycol and mixtures thereof.

Heavy metal sequestrants and crystal growth inhibitors are also suitable for use in the detergent, for example diethylenetriamine penta(methylene phosphonate), ethylenediamine tetra(methylene phosphonate) hexamethylenediamine tetra(methylene phosphonate), ethylene diphosphonate, hydroxy-ethylene-1,1-diphosphonate, nitrilotriacetate, ethylenediaminotetracetate, ethylenediamine-N,N′-disuccinate in their salt and free acid forms.

Suitable for use in the detergent composition described herein is also a corrosion inhibitor, for example organic silver coating agents (especially paraffins such as WINOG 70 sold by Wintershall, Salzbergen, Germany), nitrogen-containing corrosion inhibitor compounds (for example benzotriazole and benzimadazole—see GB-A-1137741) and Mn(II) compounds, particularly Mn(II) salts of organic ligands.

Other suitable components for use in the detergent composition herein include enzyme stabilizers, for example calcium ion, boric acid and propylene glycol.

Suitable rinse additives are known in the art. Commercial rinse aids for dishwashing typically are mixtures of low-foaming fatty alcohol polyethylene/polypropylene glycol ethers, solubilizers (for example cumene sulfonate), organic acids (for example citric acid) and solvents (for example ethanol). The function of such rinse aids is to influence the interfacial tension of the water in such a way that it is able to drain from the rinsed surfaces in the form of a thin coherent film, so that no water droplets, streaks, or films are left after the subsequent drying process. European Patent 0 197 434 B1 describes rinse aids which contain mixed ethers as surfactants. Rinse additives such as fabric softeners and the like are also contemplated and suitable for encapsulation in a film according to the disclosure herein.

Methods of Use

The films and articles described herein, as well as compositions contained therein, may be used to treat a substrate, e.g., fabric or a hard surface, for example by contacting the substrate with the film, article, and/or composition contained therein. The contacting step may occur manually or in an automatic machine, e.g., an automatic (top or front-loading) laundry machine or an automatic dishwashing machine. The contacting step may occur in the presence of water, which may be at a temperature up to about 80° C., or up to about 60° C., or up to about 40° C., or up to about 30° C., or up to about 20° C., or up to about 15° C., or up to about 10° C., or up to about 5° C. As noted above, the present films and articles made therefrom are particularly suited for cold water dissolution and therefore provide benefits in cold-water washes (e.g., from about 1° C. to about 30° C., or from about 5° C. to about 20° C.). The contacting step may be followed by a multi-rinse cycle or even by a single rinse cycle; because the film has good dissolution properties, less water is required to dissolve the film and/or release the contents contained therein.

Specific contemplated aspects of the disclosure are herein described in the following numbered paragraphs.

1. A water-soluble film comprising: a polyvinyl alcohol (PVOH) polymer; dipropylene glycol as a first plasticizer; a sugar alcohol as a second plasticizer; and a polyol as a third plasticizer, the third plasticizer being different from the first plasticizer and the second plasticizer.

2. A water-insoluble film comprising: a water-insoluble polyvinyl alcohol (PVOH) polymer (e.g., a crosslinked PVOH polymer); dipropylene glycol as a first plasticizer; a sugar alcohol as a second plasticizer; and a polyol as a third plasticizer, the third plasticizer being different from the first plasticizer and the second plasticizer.

3. The film of any of the preceding paragraphs, wherein the sugar alcohol is selected from the group consisting of isomalt, maltitol, sorbitol, xylitol, erythritol, adonitol, dulcitol, pentaerythritol, and mannitol.

4. The film of the preceding paragraph, wherein the sugar alcohol is sorbitol.

5. The film of any of the preceding paragraphs, wherein the polyol is selected from the group consisting of glycerin, diglycerin, ethylene glycol, diethylene glycol, triethyleneglycol, tetraethylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, propylene glycol, 2-methyl-1,3-propanediol, trimethylolpropane, and polyether polyols.

6. The film of the preceding paragraph, wherein the polyol is glycerin.

7. The film of any of the preceding paragraphs, wherein the sugar alcohol is sorbitol, and the polyol is glycerin.

8. The film of any of the preceding paragraphs, comprising: the polyvinyl alcohol (PVOH) polymer; dipropylene glycol as the first plasticizer; sorbitol as the second plasticizer; and glycerin as the third plasticizer; wherein the first, second, and third plasticizers are present in the film in a combined amount in a range of about 5 parts to about 50 parts total plasticizer per 100 parts total resin (phr) in the film.

9. The film of any of the preceding paragraphs, wherein the film is substantially free from plasticizers other than the than the first, second, and third plasticizers.

10. The film of any of the preceding paragraphs, wherein the film comprises a solid plasticizer which has a melting point above about 50° C.

11. The film of the preceding paragraph, wherein the solid plasticizer is also the second plasticizer.

12. The film of any of the preceding paragraphs, wherein the first, second, and third plasticizers are present in the film in a combined amount in a range of about 5 parts to about 40 parts total plasticizer per 100 parts total resin (phr) in the film.

13. The film of the preceding paragraph, wherein the first, second, and third plasticizers are present in the film in a combined amount in a range of about 10 phr to about 40 phr, or about 20 phr to about 35 phr.

14. The film of any of the preceding paragraphs, wherein: the film has an aged tensile strength of at least about 25 MPa as measured by the Aged Tensile Strength Test; and the film has a seal tear value of at least about 170% as measured by the Sum Seal Tear Test.

15. The film of the preceding paragraph, wherein the film has an aged tensile strength of at least about 30 MPa as measured by the Aged Tensile Strength Test.

16. The film of the paragraph 14 or 15, wherein: the first plasticizer is present in the film in an amount in a range of about 10 wt. % to about 40 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 10 wt. % to about 30 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 40 wt. % to about 70 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

17. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

18. The film of any of the preceding paragraphs, wherein: the second plasticizer is present in the film in an amount in a range of about 10 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

19. The film of any of the preceding paragraphs, wherein: the third plasticizer is present in the film in an amount in a range of about 25 wt. % to about 80 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

20. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 46 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 13 wt. % to about 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 28 wt. % to about 73 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

21. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 38 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 16 wt. % to about 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 28 wt. % to about 71 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

22. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 13 wt. % to about 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 28 wt. % to about 73 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

23. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 50 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 13 wt. % to about 50 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 36 wt. % to about 73 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

24. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 45 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 19 wt. % to about 52 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 35 wt. % to about 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

25. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 39 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 22 wt. % to about 38 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 39 wt. % to about 64 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

26. The film of any of the preceding paragraphs, wherein: the first plasticizer is present in the film in an amount in a range of about 13 wt. % to about 19 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; the second plasticizer is present in the film in an amount in a range of about 41 wt. % to about 52 wt. % relative to the combined amount of the first, second, and third plasticizers in the film; and the third plasticizer is present in the film in an amount in a range of about 35 wt. % to about 44 wt. % relative to the combined amount of the first, second, and third plasticizers in the film.

27. The film of any of the preceding paragraphs, wherein the film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 12° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 1300 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 25 MPa as measured by the Aged Tensile Strength Test.

28. The film of any of the preceding paragraphs, wherein the film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 1900 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 30 MPa as measured by the Aged Tensile Strength Test.

29. The film of any of the preceding paragraphs, wherein the film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of about 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least about 2500 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least about 32.5 MPa as measured by the Aged Tensile Strength Test.

30. The film of any of paragraphs 27 to 29, wherein the film has all three of the properties (a), (b), and (c).

31. The film of any of the preceding paragraphs, wherein the film further comprises one or more components selected from the group consisting of plasticizers other than the first, second, and third plasticizers, plasticizer compatibilizers, lubricants, release agents, fillers, extenders, cross-linking agents, antiblocking agents, antioxidants, detackifying agents, antifoams, nanoparticles, bleaching agents, surfactants, and combinations thereof.

32. The film of any of the preceding paragraphs, wherein the PVOH polymer comprises a PVOH homopolymer consisting essentially of vinyl alcohol monomer units and optionally vinyl acetate monomer units.

33. The film of any of the preceding paragraphs, wherein the PVOH polymer comprises a PVOH copolymer comprising an anionic monomer unit, a vinyl alcohol monomer unit, and optionally a vinyl acetate monomer unit.

34. The film of the preceding paragraph, wherein the anionic monomer is selected from the group consisting of vinyl acetic acid, maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate, dimethyl maleate, maleic anyhydride, fumaric acid, monoalkyl fumarate, dialkyl fumarate, monomethyl fumarate, dimethyl fumarate, fumaric anyhydride, itaconic acid, monomethyl itaconate, dimethyl itaconate, itaconic anhydride, vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali metal salts of the foregoing, esters of the foregoing, and combinations thereof.

35. The film of paragraph 33, wherein the anionic monomer is selected from the group consisting of acrylamido methylpropanesulfonic acids, alkali metal salts thereof, and combinations thereof.

36. The film of paragraph 33, wherein the anionic monomer is selected from the group consisting of monomethyl maleate, alkali metal salts thereof, and combinations thereof.

37. The film of any of the preceding paragraphs, wherein the PVOH polymer comprises a polymer blend comprising two or more different PVOH homopolymers.

38. The film of any of the preceding paragraphs, wherein the PVOH polymer comprises a polymer blend comprising two or more different PVOH copolymers.

39. The film of the preceding paragraph, wherein the polymer blend comprises a first PVOH copolymer comprising a first anionic monomer unit, and a second PVOH copolymer comprising a second anionic monomer unit different from the first anionic monomer unit.

40. The film of the preceding paragraph, wherein: the first anionic monomer is selected from the group consisting of acrylamido methylpropanesulfonic acids, alkali metal salts thereof, and combinations thereof; and the second anionic monomer is selected from the group consisting of monomethyl maleate, alkali metal salts thereof, and combinations thereof.

41. The film of the preceding paragraph, wherein: the first PVOH copolymer is present in an amount in a range of about 10 wt. % to about 80 wt. % of total PVOH polymers in the film; and the second PVOH copolymer is present in an amount in a range of about 20 wt. % to about 90 wt. % of total PVOH polymers in the film.

42. The film of any of the preceding paragraphs, wherein the PVOH polymer comprises a polymer blend comprising at least one PVOH homopolymer and at least one PVOH copolymer.

43. The film of any of the preceding paragraphs, wherein the PVOH polymer has a degree of hydrolysis in a range of about 75% to about 99%.

44. The film of any of the preceding paragraphs, wherein the PVOH polymer has a 4% solution viscosity at 20° C. in a range of about 4 cP to about 24 cP.

45. The film of any of the preceding paragraphs, wherein the film further comprises a water-soluble polymer which is other than a PVOH polymer.

46. The film of the preceding paragraph, wherein the water-soluble polymer is selected from the group consisting of polyethyleneimines, polyvinyl pyrrolidones, polyalkylene oxides, polyacrylamides, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polyamides, gelatines, methylcelluloses, carboxymethylcelluloses and salts thereof, dextrins, ethylcelluloses, hydroxyethyl celluloses, hydroxypropyl methylcelluloses, maltodextrins, starches, modified starches, guar gum, gum Acacia, xanthan gum, carrageenan, polyacrylates and salts thereof, copolymers thereof, blends thereof, and combinations thereof.

47. An article comprising: a film of any of the preceding paragraphs comprising a first surface of said film solvent-sealed to a second surface of the same film or to a surface of a second film of any of the preceding paragraphs.

48. An article comprising: a film of any of the preceding paragraphs in the form of a pouch defining an interior pouch volume.

49. The article of the preceding paragraph, further comprising a composition contained in the interior pouch volume.

50. An article comprising: a film of any of the preceding paragraphs and a household care composition proximal to the film.

51. A method for making a film according to any of the preceding paragraphs, the method comprising: selecting a polyvinyl alcohol (PVOH) polymer, a first plasticizer, a second plasticizer, and a third plasticizer; selecting a desired range for at least a first film property and a second film property; forming a plurality of films comprising the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at different concentrations of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer, wherein at least one of the films has a film property within the desired range for each of the first and second film properties; determining the first and second film properties for each of the formed films; identifying a film concentration for each of the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer from the formed plurality of films, the identified film concentration having a first film property and a second film property within the desired range for each property; and forming a film comprising the PVOH polymer, the first plasticizer, the second plasticizer, and the third plasticizer at the identified film concentration.

52. Use of dipropylene glycol as a plasticizer for a water-soluble polyvinyl alcohol film, in combination with a sugar alcohol plasticizer and a polyol plasticizer, for improving one or more of (a) aged melting transition delta elevation of the film as measured by the Aged Melting Transition Delta Test; (b) aged adhesion value of the film as measured by the Aged Adhesion Test; and (c) aged tensile strength of the film as measured by the Aged Tensile Strength Test.

Aged Tensile Strength Test

A water-soluble film characterized by or to be tested for tensile strength according to the Aged Tensile Strength (“ATS” or “Tensile-Aged”) Test and optionally modulus (or tensile stress) is analyzed as follows. The procedure includes the determination of tensile strength and optionally the determination of modulus at 100% elongation according to ASTM D 882 (“Standard Test Method for Tensile Properties of Thin Plastic Sheeting”) or equivalent. An INSTRON tensile testing apparatus (Model 5544 Tensile Tester or equivalent) is used for the collection of film data. A film sample of size capable to produce minimum of three test specimens is first conditioned by placing the film sample in a foil laminate pouch with minimal head space and heat sealed closed. The pouch is placed in 35° C. oven for 14 days. After the 14 days, the pouch is removed and allowed to cool to 23° C. The specimens are each cut with reliable cutting tools to ensure dimensional stability and reproducibility, and they are tested in the machine direction (MD) (where applicable) for each measurement. Tests are conducted in the standard laboratory atmosphere of 23±2.0° C. and 35±5% relative humidity. For tensile strength or modulus determination, 1″-wide (2.54 cm) samples of a single film sheet having a thickness of 3.0±0.15 mil (or 76.2±3.8 μm) are prepared. The sample is then transferred to the INSTRON tensile testing machine to proceed with testing while minimizing exposure in the 35% relative humidity environment. The tensile testing machine is prepared according to manufacturer instructions, equipped with a 500 N load cell, and calibrated. The correct grips and faces are fitted (INSTRON grips having model number 2702-032 faces, which are rubber coated and 25 mm wide, or equivalent). The samples are mounted into the tensile testing machine and analyzed to determine the tensile strength (i.e., stress required to break film) and optionally the 100% modulus (i.e., stress required to achieve 100% film elongation).

Suitable behavior of water-soluble films according to the disclosure is marked by ATS values of at least about 25 MPa, 30 MPa, or 32.5 MPa as measured by the ATS Test. Generally, higher ATS values are desirable because they correspond to stronger pouches in general and stronger pouch seals when the film is the limiting or weakest element of a seal. In various embodiments, the water-soluble film has an ATS value of at least about 25, 30, 32.5, or 35 MPa and/or up to about 30, 35, 38, 40, 45, or 50 MPa.

Sum Seal Tear Test

A water-soluble film characterized by or to be tested for seal strength according to the Sum Seal Tear (“SST” or “Sum % Seal Tears”) Test is analyzed as follows. The procedure includes the determination of seal strength as a percent (or fraction) of seals in which the film tears instead of the layers of film forming the seal peeling when pulled apart. A strong seal exhibits a tear result (i.e., enough force is applied to tear the film before a seal is peeled apart), while a weak seal exhibits a peel result (i.e., two sealed films peel apart before enough force is applied to tear the film). An INSTRON tensile testing apparatus (Model 5544 Tensile Tester or equivalent) is used for the collection of film data and an ESIPROOF proofing apparatus or equivalent with an anilox roller 140/10 is used for sealing two sheets of film with water. A film sample of size capable to produce a minimum of five test specimens is first conditioned by placing the film specimens in a foil laminate pouch with minimal head space and heat sealed closed. The pouch is placed in 38° C. oven for 11 days. After the 11 days, the pouch is removed and allowed to cool to 23° C.±2.0° C.

The SST Test is performed as follows: Prepare the test specimens by cutting four 100 mm×300 mm film sheets with the 300 mm dimension in the machine direction (MD). For two sheets, tape the four corners of one sheet to a surface. Overlay the other sheet on top of the taped sheet so the appropriate surfaces are in contact. On top of the other taped sheet, place the remaining sheet on top so that either (1) the gloss side (i.e., the substrate-contacting side of a cast film) is contacted with the matte surface side (i.e., the air-dried side of a cast film), i.e., to form and evaluate a matte-gloss seal or (2) the matte side is contacted with the matte surface (i.e., to form and evaluate a matte-matte seal). Tape one 100 mm end of the each top sheet to secure to the bottom sheet. Thread the loose end of each top sheet through the ESIPROOF proofing roller using the 140/10 anilox roller. Apply 0.5 mL of water to the doctor blade. Pull the roller at a constant speed (75 mm per second) to coat the upper film and secure to the lower sheet. Allow the film to weld for 10-15 minutes. Using a strip punch or sample cutter, cut 25.4 mm wide samples in the transverse direction (TD). Once transferred to the INSTRON testing machine proceed with testing to minimize exposure to environment. Set a 6 mm separation between the film grips and the cross head speed at 254 mm/min. Place the unsealed flaps of a specimen in the grips of the testing machine, taking care to ensure the specimen is aligned with the grips and parallel to them. Initiate the test to apply a load to the flaps to tear or separate the sealed layers. Record seal performance as a tear if at least one of the two flaps exhibits a tear in at least 25% of the flap's width. Otherwise, record seal performance as a peel.

The test is performed for both matte-gloss seal specimens and matte-matte seal specimens, both of which seal configurations are common in the formation of seals for water-soluble pouches according to the disclosure. The percent of seals which tear for each type of seal are added together to provide the SST value. For example, if 100% of the matte-gloss seals tear and 100% of the matte-matte seals tear, the SST value is 200%.

Suitable behavior of water-soluble films according to the disclosure is marked by SST values of at least about 50%, 100%, 150%, 170%, 180% or 190% and/or up to about 160%, 180% or 200% (e.g., about 170% or 180% to 200%). Within these ranges, the films exhibit a high seal strength.

Aged Melting Transition Delta Test

A water-soluble film characterized by or to be tested for an increase in melting temperature according to the Aged Melting Transition Delta Test (“AMTD” or “dTml”) Test is analyzed as follows. The AMTD value is the melting temperature T_(m1) value after two weeks of aging/annealing minus the T_(m1) value at prior to aging. The melting point of a polymer can increase as the crystallite size/number in the polymer increases. Lower values of AMTD have been associated with better sealing in the conversion process and are believed to be indicative of less growth in crystallinity and thereby providing more mobile, amorphous regions available for sealing. A lower AMTD value is favorable. For aging, a film sample is first conditioned by being placed in a foil laminate pouch with minimal head space and heat sealed closed. The pouch is placed in 35° C. oven for 14 days. After the 14 days, the pouch is removed and allowed to cool to room temperature (23.0° C.±2.0° C.).

The test is performed using a TA Instruments Q2000 differential scanning calorimeter (DSC) or equivalent with a 50 ml/min nitrogen purge and TZERO aluminum hermetic pans (available from TA Instruments) to avoid weight losses during temperature ramping. Film specimens to be tested are cut in small pieces to provide about 3-5 mg total sample that fits into the pans (e.g., about 3 stacked, cut film pieces). The DSC test is performed by (1) equilibrating at −75.00° C. and then (2) ramping at 10.00° C./min to 200.00° C. to generate DSC curves. Upon generating the curves, all transitions are recorded as T_(g), T_(m1), and T_(m2), as well as the enthalpy for T_(m1) according to standard calorimetry analysis. The DSC test is performed on the initial film prior to aging and the film after two weeks of aging at 35° C. The AMTD value is then computed as T_(m1, aged)−T_(m1, initial).

Suitable behavior of water-soluble films according to the disclosure is marked by AMTD values of about 4, 6, 8, 10, 11, or 12° C. or less and/or at least about 0, 2, 4, 6, or 8° C. (e.g., about 0, 2, or 4° C. to about 11 or 12° C.). Within these ranges, the films exhibit improved seal strength, in particular after formation into packets or pouches.

Aged Adhesion Test

A water-soluble film characterized by or to be tested for adhesion (or tackiness) according to the Aged Adhesion (“AA” or “2W-PA”) Test is analyzed as follows. The AA test value is the positive area under the curve of a tackiness (adhesion) test. The positive area is similar to or equivalent to work of adhesion. For aging, a film sample capable to produce a minimum of three test specimens is first conditioned by being placed in a foil laminate pouch with minimal head space and heat sealed closed. The pouch is placed in 35° C. oven for 14 days. After the 14 days, the pouch is removed and allowed to cool to room temperature (23.0° C.±2.0° C.). A higher AA value is favorable and is representative of seal strength.

The test is performed using a Stable Microsystems (XT+ specification) texture analyzer or equivalent fitted with a pasta firmness rig and an overhead probe spray gun (BADGER 200-3 or equivalent) for water application. The test is performed with the following standard tackiness method parameters: Coat Weight 0.04 g, Open Time 10 sec, Sealing Force 50 kg, Sealing Time 2 sec, and Curing Time 60 sec. Samples are prepared under controlled conditions (21° C., 35% RH) by cutting two film pieces of 14 cm×9 cm and then, using double-sided tape, fixing one layer to the pasta firmness rig (lower platform) and one layer to the upper probe by carefully smoothing out any potential wrinkle. Three specimen replicates are then tested according to the following procedure:

1. Position the spray gun at 20.5 cm above the lower platform;

2. Spray water in order to apply 0.04 g at the center of the lower film layer;

3. Bring upper probe down until combining film layers and apply 50 kg pressure for 2 s, with the time between water application and combining being set at 10 s;

4. Release pressure and maintain contact for 60 s (force for relaxation at 100 g);

5. Bring upper probe back-up at a constant speed of 12 mm/s; and

6. Record ‘positive area’ as the work of adhesion of the film specimen.

Suitable behavior of water-soluble films according to the disclosure is marked by AA values of at least about 1300, 1900, or 2500 g/s and/or up to about 3000, 4500, 6000, 8000, 10000, 15000 or 20000 g/s. Above these lower threshold levels (e.g., within a range also defined by an upper bound), the films exhibit improved seal strength.

EXAMPLES Example 1: Plasticizer Blend Series 1

Example 1 represents a series of water-soluble films based on a blend of PVOH homopolymers and three different plasticizers, including glycerin, sorbitol, and one from a series of different polyol plasticizers. The PVOH homopolymer blend is a 50 wt. %/50 wt. % blend of a first partially hydrolyzed PVOH homopolymer having a 13 cP 4% solution viscosity and a second partially hydrolyzed PVOH homopolymer having a 23 cP 4% solution viscosity. The films included (i) their respective PVOH homopolymer resins (100 weight parts per hundred resin weight parts (phr)), (ii) glycerin plasticizer (21.7 phr), (iii) sorbitol plasticizer (5.7 phr), (iv) a polyol plasticizer (11 phr), (v) a modified starch filler (about 2-4 phr), (vi) surfactants and other process aids (about 5-7 phr), and (vii) residual water. The polyol plasticizer was variously propylene glycol (PG), 2-methyl-1,3-propanediol (2M-1,3-PD), diethylene glycol (DEG), trimethylolpropane (TMP), dipropylene glycol (DPG), triethylene glycol (TEG), or diglycerin (DG). Total plasticizer loading was 38.4 phr. Aqueous compositions of the foregoing were cast to form 3.0±0.15 mil (or 76.2±3.8 μm) film samples, which were tested for their ATS values and SST values by the above methods. Table 1 summarizes the film properties, including the molar volume (MVol; ml/mol) of the polyol plasticizer, for Example 1.

TABLE 1 Film Data for Example 1 MVol Film Polyol (ml/mol) HSP ATS (MPa) SST (%) 1 PG 73.7 20.8 31.31 160 2 2M-1,3- 88.5 20.5 27.38 140 PD 3 DEG 95.3 21.4 29.58 60 4 TMP 121.1 20.8 24.92 140 5 DPG 131.8 20.5 30.33 200 6 TEG 134.2 21.2 23.13 160 7 DG 126.0 22.3 22.20 0

FIG. 2 of Example 1 shows that there is a generally unfavorable trend of decreasing Aged Tensile-Strength as a function of increasing molar volume. The general inverse relationship between molar volume and the tensile strength observed is consistent with the role of molar volume in affecting plasticizer function. The molar volume of a particular plasticizer (e.g., which can be determined as the inverse of plasticizer density at 25° C., expressed on a molar basis) generally relates to the size of plasticizer molecules. Larger plasticizer molecules with larger molar volumes tend to have a more tortuous path adjacent polymer chain segments (e.g., from the same or different polymer chains), which can limit the ability of the molecule to function as a plasticizer. FIG. 2 shows a reasonable R² correlation value of 88% when DPG is eliminated from the data trend. FIG. 2 illustrates that DPG clearly stands alone from among other polyol plasticizers in the blend, because it has a surprisingly high Aged Tensile-Strength notwithstanding its relatively high molar volume and the substantially lower Aged Tensile-Strengths of other polyol plasticizers having comparable molar volumes (TMP, DG, TEG). Similar to plasticizer molar volume, the Hansen Solubility Parameter (“HSP” or “δ_(T)”) has been used to select plasticizers. As seen in Table 2, however, there is no identifiable correlation between the HSP value and the Aged Tensile Strength.

FIG. 3 of Example 1 further shows that DPG has a surprisingly high Sum Seal Tear value. The SST value is the sum of percentage water seals that fail in the tear mode in matte-matte seals and matte-gloss seals, which represent common seal configurations for water-soluble film packets. The highest possible SST value is 200%, and this was achieved with only DPG as the third plasticizer in the combination of glycerin, polyol and sorbitol.

Example 2: Plasticizer Blend Series 2

Example 2 represents a series of water-soluble films based on a blend of PVOH homopolymers and three different plasticizers, including glycerin, one from a series of sugar alcohol plasticizers, and propylene glycol (PG) or dipropylene glycol (DPG). The PVOH homopolymer blend is a 50 wt. %/50 wt. % blend of a first partially hydrolyzed PVOH homopolymer having a 13 cP 4% solution viscosity and a second partially hydrolyzed PVOH homopolymer having a 23 cP 4% solution viscosity. The films included (i) their respective PVOH homopolymer resins (100 weight parts per hundred resin weight parts (phr)), (ii) glycerin plasticizer (21.7 phr), (iii) a sugar alcohol plasticizer (5.7 phr), (iv) propylene glycol or dipropylene glycol plasticizer (11 phr), (v) a modified starch filler (about 2-4 phr), (vi) surfactants and other process aids (about 5-7 phr), and (vii) residual water. The sugar alcohol was variously sorbitol (S), xylitol (X), or mannitol (M). Total plasticizer loading was 38 phr. Aqueous compositions of the foregoing were cast to form 3.0±0.15 mil (or 76.2±3.8 μm) film samples, which were tested for their SST values by the above method. Table 2 summarizes the film properties for Example 2, and it shows that films including a combination of sorbitol and dipropylene glycol achieve the maximum possible SST value of 200%.

TABLE 2 Film Data for Example 2 Film Sugar Alcohol Polyol SST (%) 1 S PG 160 2 X PG 20 3 M PG 0 4 S DPG 200

Example 3: Plasticizer Blend Series 3

Example 3 represents a series of water-soluble films based on a blend of PVOH copolymers and three different plasticizers, including glycerin, one from a series of sugar alcohol plasticizers, and dipropylene glycol. The PVOH copolymer blend is a 80 wt. %/20 wt. % blend of a first partially hydrolyzed PVOH copolymer including monomethyl maleate (sodium salt) comonomer (MMM) and a second partially hydrolyzed PVOH copolymer including an acrylamido methylpropanesulfonic acid (sodium salt) comonomer (AMPS). The films included (i) their respective PVOH copolymer resins (100 weight parts per hundred resin weight parts (phr)), (ii) glycerin plasticizer (16.2 phr), (iii) a sugar alcohol plasticizer (10.4 phr), (iv) dipropylene glycol plasticizer (10.4 phr), (v) a modified starch filler (about 2-4 phr), (vi) surfactants and other process aids (about 5-7 phr), and (vii) residual water. The sugar alcohol was variously sorbitol (S), xylitol (X), or mannitol (M). Total plasticizer loading was 37 phr. Aqueous compositions of the foregoing were cast to form 3.0±0.15 mil (or 76.2±3.8 μm) film samples, which were tested for their SST values by the above method. Table 3 summarizes the film properties for Example 3, and it shows that films including a combination of sorbitol and dipropylene glycol achieve substantially improved SST values compared to other sugar alcohol plasticizers (e.g., 60% for sorbitol, 0% for xylitol and mannitol).

TABLE 3 Film Data for Example 3 Film Sugar Alcohol SST (%) 1 S 60 2 X 0 3 M 0

Example 4: Plasticizer Blend Series 4

Example 4 represents a series of water-soluble films based on a blend of PVOH copolymers and three different plasticizers, including glycerin, sorbitol, and dipropylene glycol. The PVOH copolymer blend is a 80 wt. %/20 wt. % blend of a first partially hydrolyzed PVOH copolymer including monomethyl maleate (sodium salt) comonomer (MMM) and a second partially hydrolyzed PVOH copolymer including an acrylamido methylpropanesulfonic acid (sodium salt) comonomer (AMPS). The films included (i) their respective PVOH copolymer resins (100 weight parts per hundred resin weight parts (phr)), (ii) glycerin plasticizer (G; variable phr), (iii) sorbitol plasticizer (S; variable phr), (iv) dipropylene glycol plasticizer (DPG; variable phr), (v) a modified starch filler (about 2-4 phr), (vi) surfactants and other process aids (about 5-7 phr), and (vii) residual water. Total plasticizer loading was 29.6 phr, 37.0 phr, or 44.4 phr, and the relative ratios between the three plasticizers were varied in the films. Aqueous compositions of the foregoing were cast to form 3.0±0.15 mil (or 76.2±3.8 μm) film samples, which were tested for their ATS values, AA values, AMTD values, SST values by the above methods. Table 4 summarizes the film properties for Example 4, and it shows that films including a combination of sorbitol and dipropylene glycol achieve a combination of favorable properties over a range of plasticizer blend relative compositions and total loadings. For example, films according to the disclosure can be formulated to have at least two of the properties: (a) an AMTD value of about 12° C. or 11° C. less, (b) an AA value of at least about 1300 g/s, 1900 g/s, or 2500 g/s, and (c) an ATS value of at least about 25 MPa, 30 MPa, or 32.5 MPa.

TABLE 4 Film Data for Example 4 Total G S DPG Plast. ATS SST AMTD Film (phr) (phr) (phr) (phr) (MPa) (%) (° C.) AA (g/s) 1 8.6 17.0 4.0 29.6 32.0 0 9.93 2896 2 21.6 4.0 4.0 29.6 28.9 60 7.63 2483 3 8.6 4.0 17.0 29.6 32.1 80 12.28 1981 4 12.9 8.3 8.3 29.6 32.3 20 9.37 2149 5 10.8 21.3 5.0 37.0 36.4 0 13.32 1276 6 27.0 5.0 5.0 37.0 26.1 0 4.99 1193 7 10.8 5.0 21.3 37.0 30.7 20 10.63 788 8 16.2 10.4 10.4 37.0 25.5 60 11.92 1406 9 12.9 25.5 6.0 44.4 27.4 0 6.35 909 10 32.4 6.0 6.0 44.4 22.9 0 9.59 644 11 12.9 6.0 25.5 44.4 26.3 20 −1.2 211 12 19.4 12.5 12.5 44.4 25.3 0 9.89 874

Example 4 illustrates a series of films in which the ratios of the three plasticizers (G, S, DPG) were varied and evaluated at three total plasticizer loadings (29.6, 37.0, and 44.4 phr). As generally seen in Table 4, the ATS value, the AMTD value, and the AA value generally improve with lower total plasticizer (e.g., 29.6 phr is better than 37.0 phr which is better than 44.4 phr in Example 4), in particular for combinations of properties and with respect to threshold properties representing desirable end-use characteristics for the properties. Based on the results of Example 4, first, second, and third target threshold levels for the ATS, AMTD, and AA values were identified: (1) at least 25 MPa, 12° C. or less, and at least 1300 g/s; (2) at least 30 MPa, 11° C. or less, and at least 1900 g/s; and (3) at least 32.5 MPa, 11° C. or less, and at least 2500 g/s.

FIG. 4 for Example 4 shows contour plots of AMTD (dTml), AA (2W-PA), and ATS (Tensile-Aged) values. Each plot has an arrow that shows the direction of favorable performance that is decreasing AMTD, increasing AA and increasing ATS. There are two particularly notable points in this series of plots. Firstly, using AMTD as an example, it is apparent that at 44.4 phr the arrow is pointed down while at 37.0 phr the arrow is descending from left to right, and finally at 29.6 phr the arrow is pointing up. The simplex plots and the corresponding Table 4 do not identify a formulation that simultaneously optimizes all of individual performance criteria (e.g., maximizing AA and ATS values while minimizing the AMTD value). However there is a formulation space wherein two or three of the performance criteria meet or exceed desirable threshold values.

FIGS. 5-8 illustrate overlaid contour plots with each of three target threshold levels for the ATS, AMTD, and AA values described above. The white space in a plot shows the region where all three criteria are met at that level of total plasticizer and ratio of plasticizers, while the gray space show the region where at least one criterion is not met. For example, in FIG. 5, the line labeled “A” indicates the boundary between film compositions having an AMTD value greater than 12° C. (gray region) and those having an AMTD value lower than 12° C. (white region). At the lowest level plasticizer loading level (29.6 phr), decreasing regions of white area from left to right correspond to the first, second, and third target threshold levels, respectively.

Example 5: PVOH Copolymer Blend Series

Example 5 represents a series of water-soluble films based on a blend of PVOH copolymers and three different plasticizers, including glycerin, sorbitol, and dipropylene glycol. The PVOH copolymer blend is a variable-ratio blend of a first partially hydrolyzed PVOH copolymer including monomethyl maleate (sodium salt) comonomer (MMM) and a second partially hydrolyzed PVOH copolymer including an acrylamido methylpropanesulfonic acid (sodium salt) comonomer (AMPS). The films included (i) their respective PVOH copolymer resins (100 weight parts per hundred resin weight parts (phr)), (ii) glycerin plasticizer (16.2 phr), (iii) sorbitol plasticizer (10.4 phr), (iv) dipropylene glycol plasticizer (10.4 phr), (v) a modified starch filler (about 2-4 phr), (vi) surfactants and other process aids (about 5-7 phr), and (vii) residual water. Total plasticizer loading was 37 phr. The amount of PVOH-co-MMM in the copolymer blend ranged from 0 wt. % to 100 wt. %. Aqueous compositions of the foregoing were cast to form 3.0±0.15 mil (or 76.2±3.8 μm) film samples, which were tested for their ATS values, AA values, AMTD values, SST values by the above methods. Table 5 summarizes the film properties for Example 5, and it shows that films including a combination of sorbitol and dipropylene glycol achieve a combination of favorable properties over a range of copolymer blend compositions.

TABLE 5 Film Data for Example 5 PVOH -co-MMM PVOH-co-AMPS ATS SST AMTD AA Film (wt. %) (wt. %) (MPa) (%) (° C.) (g/s) 1 0 100 17.5 0 10.3 1055 2 80 20 25.5 60 11.92 1406 3 50 50 25.4 0 7.84 759 4 20 80 22.1 0 9.12 611 5 100 0 26.8 20 16.4 1677

FIG. 9 of Example 5 shows that the response of both the AMTD values and the ATS values is non-linear as function of PVOH-co-MMM (% M) content. This non-linear response is a substantially favorable deviation relative to a linearly interpolated baseline from the Rule-of Mixtures (ROM). There is a substantial decrease in the AMTD value over a range of about 20 wt. % to 80 wt. % PVOH-co-MMM and there is a substantial increase in the ATS value over a range of about 20 wt. % to 50 wt. % PVOH-co-MMM. FIG. 10 of Example 5 shows that the 80 wt. %/20 wt. % blend of PVOH-co-MMM/PVOH-co-AMPS shows a surprisingly good SST value compared to all other ratios tested. Although the SST value of 60% is lower compared to the 200% SST value from Example 1, the 80 wt. %/20 wt. % blend stands out for relatively good performance in the series of Example 5.

Example 6: Illustrative Compositions

Tables 6-14 show illustrative compositions that may be combined with the articles described herein. For example, the compositions below, which are intended to be non-limiting examples, may be encapsulated in the water-soluble films described herein, for example in a pouch.

A bleach additive can include the ingredients presented in Table 6.

TABLE 6 A Wt. % Sodium Percarbonate 25 Bleach activator¹ 7 Sodium Carbonate 15 Sodium Citrate 10 Zeolite 10 Sodium Sulfate 15 Enzymes 2 Optical brighteners 2 Miscellaneous To 100 ¹Tetraacetyl ethylene diamine

Granular laundry detergents can include the ingredients presented in Table 7.

TABLE 7 B C D E F G (wt %) (wt %) (wt %) (wt %) (wt %) (wt %) Linear alkylbenzenesulfonate 8 7.1 7 6.5 7.5 7.5 AE3S 0 4.8 0 5.2 4 4 C12-14 Alkylsulfate 1 0 1 0 0 0 AE7 2.2 0 3.2 0 0 0 C₁₀₋₁₂ Dimethyl 0.75 0.94 0.98 0.98 0 0 hydroxyethylammonium chloride Crystalline layered silicate (d- 4.1 0 4.8 0 0 0 Na₂Si₂O₅) Zeolite A 5 0 5 0 2 2 Citric Acid 3 5 3 4 2.5 3 Sodium Carbonate 15 20 14 20 23 23 Silicate 2R (SiO₂:Na₂O at ratio 2:1) 0.08 0 0.11 0 0 0 Soil release agent 0.75 0.72 0.71 0.72 0 0 Acrylic Acid/Maleic Acid Copolymer 1.1 3.7 1.0 3.7 2.6 3.8 Carboxymethylcellulose 0.15 1.4 0.2 1.4 1 0.5 Protease - Purafect ® (84 mg active/g) 0.2 0.2 0.3 0.15 0.12 0.13 Amylase - Stainzyme Plus ® (20 mg 0.2 0.15 0.2 0.3 0.15 0.15 active/g) Lipase - Lipex ® (18.00 mg active/g) 0.05 0.15 0.1 0 0 0 Amylase - Natalase ® (8.65 mg 0.1 0.2 0 0 0.15 0.15 active/g) Cellulase - Celluclean ™ (15.6 mg 0 0 0 0 0.1 0.1 active/g) TAED 3.6 4.0 3.6 4.0 2.2 1.4 Percarbonate 13 13.2 13 13.2 16 14 Na salt of Ethylenediamine-N,N′- 0.2 0.2 0.2 0.2 0.2 0.2 disuccinic acid, (S,S) isomer (EDDS) Hydroxyethane di phosphonate 0.2 0.2 0.2 0.2 0.2 0.2 (HEDP) MgSO₄ 0.42 0.42 0.42 0.42 0.4 0.4 Perfume 0.5 0.6 0.5 0.6 0.6 0.6 Suds suppressor agglomerate 0.05 0.1 0.05 0.1 0.06 0.05 Soap 0.45 0.45 0.45 0.45 0 0 Sulphonated zinc phthalocyanine 0.0007 0.0012 0.0007 0 0 0 (active) S-ACMC 0.01 0.01 0 0.01 0 0 Direct Violet 9 (active) 0 0 0.0001 0.0001 0 0 Sulfate/Water & Miscellaneous Balance to 100

Liquid laundry detergents can include the ingredients presented in Table 8.

TABLE 8 H I J K L M Wt. % Wt. % Wt. % Wt. % Wt. % Wt. % Glycerol 3 5 6.1 0.6 5 5.3 1,2 Propanediol 16 14 15.9 12 10 Citric acid 1 1.2 0.5 0.5 Isopropanol 7.7 NaOH 0.5 1 Marlipal C₁₂₋₁₄EO₇ 22 11.8 14 20.1 C₁₃₋₁₅EO₉ 1 15 C₉₋₁₁EO₉ 72 Linear alkyl benzene 16 25 14.5 23 24.6 sulfonic acid¹ C₁₂₋₁₈ Fatty acid 16 5 12.5 6 16.4 C₁₂₋₁₄ alkyl 11.1 9 ethoxy 3 sulfate Enzymes 2.5 1.5 1.3 2.0 1.5 2.0 Polyethyleneimine 2 5.0 3.0 ethoxylate PEI 600 E20 Diethylenetriamine 0.9 1 Pentaacetic Acid Dequest 2010 1.5 1 1.1 Optical brightening 1 1.2 2.5 0.5 0.2 agent MgCl₂ 0.7 0.2 Potassium sulfite 0.5 0.35 0.2 Structurant 0.21 0.13 0.15 Silicone softening 2.5 agent (PDMS) Water 8 10 7 6 9 Miscellaneous (dyes, To 100 To 100 To 100 To 100 To 100 To 100 aesthetics, perfume etc) Monoethanol amine To pH To pH 7.5 To pH 7.4 To pH 7.6 To pH 7.6 To pH 7.6 7.6 ¹Preferred LAS also comprise an alkyl group comprising from about 9 to about 15 carbon atoms, in straight chain configuration.

The detergents can include the formulation presented in Table 9.

TABLE 9 N Wt. % Dimethyl monoethyl ether 73.87 Sodium lauryl sulfate 6.00 Dimethyl glyoxime 1.00 Isopropyl alcohol 0.5 Triazine stilbene (Tinopal UNPA- 0.4 GX) Monoethanol amine 1.52 Linear alcohol ethoxylate 13.61 (Surfonic LF-17) d-limonene 3.00

The composition can include the formulation presented in Table 10.

TABLE 10 O P Wt. % Wt. % Cationic Softener Active¹ 65.0 65.0 Fatty Acid² 1.8 1.8 TMPD³ 14.7 14.7 Cocoamide 6EO⁴ 4.05 4.05 Perfume 5 2.5 Perfume Microcapsules — 1.25 Dye 0.001 0.001 Hexylene Glycol⁶ 5.63 5.6 Ethanol⁶ 5.63 5.6 ¹Di(acyloxyethyl)(2-hydroxy ethyl) methyl ammonium methyl sulfate wherein the acyl group is derived from partially hydrogenated canola fatty acid. ²Partially hydrogenated canola fatty acid. ³2,2,4-trimethyl-1,3-pentanediol ⁴PEG 6 cocamide—polyethylene glycol amide of coconut fatty acid. ⁵Sodium salt of hydroxyethane diphosphonic acid ⁶Material included with softening active by supplier.

Multi-compartment pouches can contain a plurality of benefit agents. By way of a non-limiting example, a two- or three-component pouch may contain the formulations presented in Table 11 in separate enclosures, where dosage is the amount of the formulation in the respective enclosure.

TABLE 11 Q R S 3 compartments 2 compartments 3 compartments Compartment # 1 2 3 1 2 1 2 3 Dosage (g) 34.0 3.5 3.5 30.0 5.0 25.0 1.5 4.0 Ingredients Weight % Alkylbenzene sulfonic acid 20.0 20.0 20.0 10.0 20.0 20.0 Alkyl sulfate 2.0 C12-14 alkyl 7-ethoxylate 17.0 17.0 17.0 17.0 17.0 Cationic surfactant 1.0 Zeolite A 10.0 C12-18 Fatty acid 13.0 13.0 13.0 18.0 18.0 Sodium acetate 4.0 enzymes 0-3 0-3 0-3 0-3 0-3 Sodium Percarbonate 11.0 TAED 4.0 Organic catalyst¹ 1.0 PAP granule² 50 Polycarboxylate 1.0 Polyethyleneimine ethoxylate³ 2.2 2.2 2.2 Hydroxyethane diphosphonic 0.6 0.6 0.6 0.5 acid Ethylene diamine 0.4 tetra(methylene phosphonic) acid Brightener 0.2 0.2 0.2 0.3 0.3 Mineral oil Hueing dye⁴ 0.05 0.035 0.12 Perfume 1.7 1.7 0.6 1.5 Water and minors 10.0 10.0 10.0 4.0 (antioxidant, aesthetics, . . . ) Buffers (sodium To pH 8.0 for liquids carbonate, To RA >5.0 for powders monoethanolamine)⁵ Solvents (1,2 propanediol, To 100% ethanol) for liquids, sodium sulfate for powders ¹Sulfuric acid mono-[2-(3,4-dihydro-isoquinolin-2-yl)-1-(2-ethyl-hexyloxymethyl)-ethyl]ester as described in U.S. Pat. No. 7,169,744 ²PAP = Phtaloyl-Amino-Peroxycaproic acid, as a 70% active wet cake ³Polyethylenimine (MW = 600) with 20 ethoxylate groups per —NH. ⁴Ethoxylated thiophene, EO (R₁ + R₂) = 5 ⁵RA = Reserve Alkalinity (g NaOH/dose)

In another embodiment of multicomponent pouches, the respective enclosures can be filled with liquid and solid benefit agents. Non-limiting examples of two compartment pouches, where one enclosure is filled with a liquid and one is filled with a solid, include combinations of the formulations presented in Tables 12 and 13.

TABLE 12 T U V W Liquid formulation XL1 XL2 XL3 XL4 dosage 10 g 5 g 15 g 7 g Wt % Wt % Wt % Wt % Marlipal C24-7 74 20 14 Non ionic surfactant Neodol 55 23-5 Anionic surfactant¹ 20 20 25 Propane diol 10 4 22 10 Glycerol 2 5 5 Soil dispersant² 2 Amphiphilic alkoxylated 5 grease cleaning polymer³ Fatty acid 10 20 Enzymes 3 Structurant 3 Perfume 7 10 Water 2 3 5 Monoethanol amine To pH 7.5 Minors To 100% ¹Linear C11-13 alkyl benzene sulfonic acid ²(bis(C₂H₅O)(C₂H₄O)_(n)(CH₃)—N⁺—CxH2x—N⁺—(CH₃)-bis((C₂H₅O)(C₂H₄O)_(n)), wherein n = from 15 to 30, and x = from 3 to 8. ³Random graft copolymer is a polyvinyl acetate grafted polyethylene oxide copolymer having a polyethylene oxide backbone and multiple polyvinyl acetate side chains. The molecular weight of the polyethylene oxide backbone is about 6000 and the weight ratio of the polyethylene oxide to polyvinyl acetate is about 40 to 60 and no more than 1 grafting point per 50 ethylene oxide units.

TABLE 13 X Y Z AA Powder formulation XP1 XP2 XP3 XP4 Dosage 35 g 25 g 40 g 30 g Wt % Wt % Wt % Wt % Anionic surfactant 20 20 20 Cationic surfactant 1.5 1.5 Bleach agent 20 36 36 36 Chelating agent 0.8 2 2 2 Enzyme 10 10 10 Sodium carbonate 6 4 4 Sodium bicarbonate 4 4 Zeolite 40 20 15 15 Fluorescent whitening agent 0.5 3 1 Polymers 2 5 5 Sodium sulfate 15 Minors To 100%

A hard surface cleaning composition, which may be used by professionals, can include the formulation presented in Table 14.

TABLE 14 Ingredient Name WT % C10 alkyl alcohol-8-ethoxylate 55.0 Linear alkylbenzene sulfonic acid 9.0 Monoethanolamine 2.4 1,2 propanediol 9.0 Glycerol 7.5 C1218 alkyl fatty acid 2.5 Dye 0.1 Perfume 2.2 Water Balance

The foregoing description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as modifications within the scope of the invention may be apparent to those having ordinary skill in the art.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise” and variations such as “comprises” and “comprising” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Throughout the specification, where compositions are described as including components or materials, it is contemplated that the compositions can also consist essentially of, or consist of, any combination of the recited components or materials, unless described otherwise. Likewise, where methods are described as including particular steps, it is contemplated that the methods can also consist essentially of, or consist of, any combination of the recited steps, unless described otherwise. The invention illustratively disclosed herein suitably may be practiced in the absence of any element or step which is not specifically disclosed herein.

The practice of a method disclosed herein, and individual steps thereof, can be performed manually and/or with the aid of or automation provided by electronic equipment. Although processes have been described with reference to particular embodiments, a person of ordinary skill in the art will readily appreciate that other ways of performing the acts associated with the methods may be used. For example, the order of various of the steps may be changed without departing from the scope or spirit of the method, unless described otherwise. In addition, some of the individual steps can be combined, omitted, or further subdivided into additional steps.

All patents, publications and references cited herein are hereby fully incorporated by reference. In case of conflict between the present disclosure and incorporated patents, publications and references, the present disclosure should control. 

What is claimed:
 1. A water-soluble film comprising: a polyvinyl alcohol (PVOH) polymer; dipropylene glycol as a first plasticizer; a sugar alcohol as a second plasticizer; and a polyol as a third plasticizer, the third plasticizer being different from the first plasticizer and the second plasticizer; wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 46 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the third plasticizer is present in the water-soluble film in an amount in a range of 28 wt. % to 73 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; and the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least 1900 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least 30 MPa as measured by the Aged Tensile Strength Test.
 2. The water-soluble film of claim 1, wherein the sugar alcohol is selected from the group consisting of isomalt, maltitol, sorbitol, xylitol, erythritol, adonitol, dulcitol, pentaerythritol, and mannitol.
 3. The water-soluble film of claim 2, wherein the sugar alcohol is sorbitol.
 4. The water-soluble film of claim 1, wherein the polyol is selected from the group consisting of glycerin, diglycerin, ethylene glycol, diethylene glycol, triethyleneglycol, tetraethylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, propylene glycol, 2-methyl-1,3-propanediol, trimethylolpropane, and polyether polyols.
 5. The water-soluble film of claim 4, wherein the polyol is glycerin.
 6. The water-soluble film of claim 1, wherein the sugar alcohol is sorbitol, and the polyol is glycerin.
 7. The water-soluble film of claim 1, comprising: the polyvinyl alcohol (PVOH) polymer; dipropylene glycol as the first plasticizer; sorbitol as the second plasticizer; and glycerin as the third plasticizer; wherein the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of 5 parts to 50 parts total plasticizer per 100 parts total resin (phr) in the water-soluble film.
 8. The water-soluble film of claim 1, wherein the water-soluble film is substantially free from plasticizers other than the first, second, and third plasticizers.
 9. The water-soluble film of claim 1, wherein the water-soluble film comprises a solid plasticizer which has a melting point above 50° C.
 10. The water-soluble film of claim 9, wherein the solid plasticizer is also the second plasticizer.
 11. The water-soluble film of claim 1, wherein the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of 5 parts to 40 parts total plasticizer per 100 parts total resin (phr) in the water-soluble film.
 12. The water-soluble film of claim 11, wherein the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of 10 phr to 40 phr.
 13. The water-soluble film of claim 11, wherein the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of 20 phr to 35 phr.
 14. The water-soluble film of claim 1, wherein: the water-soluble film has an aged tensile strength of at least 25 MPa as measured by the Aged Tensile Strength Test; and the water-soluble film has a seal tear value of at least 170% as measured by the Sum Seal Tear Test.
 15. The water-soluble film of claim 14, wherein the water-soluble film has an aged tensile strength of at least 30 MPa as measured by the Aged Tensile Strength Test.
 16. The water-soluble film of claim 1, wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 38 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 16 wt. % to 58 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; and the third plasticizer is present in the water-soluble film in an amount in a range of 28 wt. % to 71 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film.
 17. The water-soluble film of claim 1, wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 45 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 19 wt. % to 52 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; and the third plasticizer is present in the water-soluble film in an amount in a range of 35 wt. % to 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film.
 18. The water-soluble film of claim 1, wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 39 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 22 wt. % to 38 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; and the third plasticizer is present in the water-soluble film in an amount in a range of 39 wt. % to 64 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film.
 19. The water-soluble film of claim 1, wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 13 wt. % to 19 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 41 wt. % to 52 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; and the third plasticizer is present in the water-soluble film in an amount in a range of 35 wt. % to 44 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film.
 20. The water-soluble film of claim 1, wherein the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of 12° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least 1300 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least 25 MPa as measured by the Aged Tensile Strength Test.
 21. The water-soluble film of claim 1, wherein the water-soluble film has at least two of the three properties (a), (b), and (c): (a) an aged melting transition delta elevation of 11° C. or less as measured by the Aged Melting Transition Delta Test; (b) an aged adhesion value of at least 2500 g/s as measured by the Aged Adhesion Test; and (c) an aged tensile strength of at least 32.5 MPa as measured by the Aged Tensile Strength Test.
 22. The water-soluble film of claim 20, wherein the water-soluble film has all three of the properties (a), (b), and (c).
 23. The water-soluble film of claim 1, wherein the water-soluble film further comprises one or more components selected from the group consisting of plasticizers other than the first, second, and third plasticizers, plasticizer compatibilizers, lubricants, release agents, fillers, extenders, cross-linking agents, antiblocking agents, antioxidants, detackifying agents, antifoams, nanoparticles, bleaching agents, surfactants, and combinations thereof.
 24. The water-soluble film of claim 1, wherein the PVOH polymer comprises a PVOH homopolymer consisting essentially of vinyl alcohol monomer units and optionally vinyl acetate monomer units.
 25. The water-soluble film of claim 1, wherein the PVOH polymer comprises a PVOH copolymer comprising an anionic monomer unit, a vinyl alcohol monomer unit, and optionally a vinyl acetate monomer unit.
 26. The water-soluble film of claim 25, wherein the anionic monomer is selected from the group consisting of vinyl acetic acid, maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate, dimethyl maleate, maleic anyhydride, fumaric acid, monoalkyl fumarate, dialkyl fumarate, monomethyl fumarate, dimethyl fumarate, fumaric anyhydride, itaconic acid, monomethyl itaconate, dimethyl itaconate, itaconic anhydride, vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali metal salts of the foregoing, esters of the foregoing, and combinations thereof.
 27. The water-soluble film of claim 25, wherein the anionic monomer is selected from the group consisting of acrylamido methylpropanesulfonic acids, alkali metal salts thereof, and combinations thereof.
 28. The water-soluble film of claim 25, wherein the anionic monomer is selected from the group consisting of monomethyl maleate, alkali metal salts thereof, and combinations thereof.
 29. The water-soluble film of claim 1, wherein the PVOH polymer comprises a polymer blend comprising two or more different PVOH homopolymers.
 30. The water-soluble film of claim 1, wherein the PVOH polymer comprises a polymer blend comprising two or more different PVOH copolymers.
 31. The water-soluble film of claim 30, wherein the polymer blend comprises a first PVOH copolymer comprising a first anionic monomer unit, and a second PVOH copolymer comprising a second anionic monomer unit different from the first anionic monomer unit.
 32. The water-soluble film of claim 31, wherein: the first anionic monomer is selected from the group consisting of acrylamido methylpropanesulfonic acids, alkali metal salts thereof, and combinations thereof; and the second anionic monomer is selected from the group consisting of monomethyl maleate, alkali metal salts thereof, and combinations thereof.
 33. The water-soluble film of claim 32, wherein: the first PVOH copolymer is present in an amount in a range of 10 wt. % to 80 wt. % of total PVOH polymers in the film; and the second PVOH copolymer is present in an amount in a range of 20 wt. % to 90 wt. % of total PVOH polymers in the film.
 34. The water-soluble film of claim 1, wherein the PVOH polymer has a degree of hydrolysis in a range of 75% to 99%.
 35. The water-soluble film of claim 1, wherein the PVOH polymer has a 4% solution viscosity at 20° C. in a range of 4 cP to 24 cP.
 36. The water-soluble film of claim 1, wherein the water-soluble film further comprises a water-soluble polymer which is other than a PVOH polymer.
 37. The water-soluble film of claim 36, wherein the water-soluble polymer is selected from the group consisting of polyethyleneimines, polyvinyl pyrrolidones, polyalkylene oxides, polyacrylamides, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polyamides, gelatines, methylcelluloses, carboxymethylcelluloses and salts thereof, dextrins, ethylcelluloses, hydroxyethyl celluloses, hydroxypropyl methylcelluloses, maltodextrins, starches, modified starches, guar gum, gum Acacia, xanthan gum, carrageenan, polyacrylates and salts thereof, copolymers thereof, blends thereof, and combinations thereof.
 38. An article comprising: a water-soluble film of claim 1 comprising a first surface of said film solvent-sealed to a second surface of the same film or to a surface of a second film of claim
 1. 39. An article comprising: a water-soluble film of claim 1 in the form of a pouch defining an interior pouch volume.
 40. The article of claim 39, further comprising a composition contained in the interior pouch volume.
 41. A water-soluble film comprising: a polyvinyl alcohol (PVOH) polymer; dipropylene glycol as a first plasticizer; a sugar alcohol as a second plasticizer; and a polyol as a third plasticizer, the third plasticizer being different from the first plasticizer and the second plasticizer; wherein: the first plasticizer is present in the water-soluble film in an amount in a range of 10 wt. % to 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the second plasticizer is present in the water-soluble film in an amount in a range of 10 wt. % to 65 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the third plasticizer is present in the water-soluble film in an amount in a range of 25 wt. % to 80 wt. % relative to the combined amount of the first, second, and third plasticizers in the water-soluble film; the first, second, and third plasticizers are present in the water-soluble film in a combined amount in a range of 10 phr to 40 phr; and the water-soluble film has all three properties (a), (b), and (c): (a) an aged melting transition delta elevation of 12° C. or less as measured by the Aged Melting Transition Delta Test, (b) an aged adhesion value of at least 1300 g/s as measured by the Aged Adhesion Test, and (c) an aged tensile strength of at least 25 MPa as measured by the Aged Tensile Strength Test.
 42. The water-soluble film of claim 41, wherein: the second plasticizer comprises sorbitol; and the third plasticizer comprises glycerin. 